Kentucky Educational Television (KET) is a statewide television network serving the U.S. commonwealth of Kentucky as a member of PBS. It is operated by the Kentucky Authority for Educational Television, an agency of the Kentucky state government, which provides more than half of its annual funding. KET is the dominant public broadcaster in the commonwealth, with transmitters covering the vast majority of the state as well as parts of adjacent states; the only other PBS member in Kentucky is WKYU-TV (channel 24) in Bowling Green. KET is the largest PBS state network in the United States; the broadcast signals of its sixteen stations cover almost all of the state, as well as parts of Illinois, Indiana, Missouri, Ohio, Tennessee, Virginia, and West Virginia. The network's offices, network center, and primary studio facilities are located at the O. Leonard Press Telecommunications Center on Cooper Drive in Lexington; KET also has production centers in Louisville and at the Kentucky State Capitol Annex in Frankfort.

The plan for a statewide educational broadcaster was first conceived in 1959 by O. Leonard Press, who served as the founding director for the Kentucky Authority for Educational Television when it was established in 1962 and remained with KET for three decades. Broadcasting began on September 23, 1968, and the network grew into a force in educational, cultural, and public affairs broadcasting in the state. Some of its educational programs, such as distance learning and adult education, attracted national interest. In 1997, KET took over WKPC-TV, which had formerly been a separate public television station in Louisville; in the years that followed, KET became the first digital broadcaster in Kentucky. In addition to offering national programming from PBS and other distributors, KET produces programs on Kentucky public affairs and culture as well as educational content. One of its four channels is the Kentucky Channel, which covers the Kentucky General Assembly. Beyond state government support, it receives funding from supporting viewers and, until 2025, the Corporation for Public Broadcasting.

Interest in educational television in Kentucky existed but was later compared to some other states. In 1953, an educational figure in Louisville told Bill Ladd of The Courier Journal, "I just hope that Arkansas, Mississippi, and Tennessee don't get so far ahead of us that we can't ever catch up. I hope that Kentucky doesn't start off 48th in educational television." While Jefferson County, home to Louisville, began the process to build what became WFPK-TV (now WKPC-TV) on channel 15 in 1957, and the station signed on the next year, the impetus for what became KET came on July 22, 1959, when O. Leonard Press, the director of the radio department at the University of Kentucky (UK)—owner of educational radio station WBKY, on air since 1940—proposed a statewide educational television network that would include studios at the university, interconnection with other universities, and a transmitter system to deliver educational programs to schools. This service was conceived along the lines of Alabama Educational Television, which had started in 1955 as the first statewide educational network. Press touted a system incorporating WFPK-TV as well as complete coverage of the Commonwealth with the capacity to "stamp out illiteracy" and ensure universal teaching of basic school subjects. He also pushed for the entire network to be built at once to ensure that rural areas, which most needed such a service, were just as well-served as Kentucky's population centers.

The network took an important step forward when the Federal Communications Commission (FCC) agreed to designate 10 new UHF television channels in the state for non-commercial educational use in August 1961; the original design did not include the transmitters at Elizabethtown or Owenton (as the existing WFPK-TV was included), though it did provide for programs to originate from Lexington, Louisville, or Murray. The plan gained the support of governor Bert T. Combs, and the 1962 Kentucky General Assembly passed a trio of bills to set up the Kentucky Authority for Educational Television, enable the State Board of Education to lease facilities, and allow the state to issue revenue bonds to finance construction. It was hoped to begin KET broadcasts by December 1963, but difficulties mounted, including the refusal of the Midwest Program on Airborne Television Instruction (MPATI) to sign a contract to furnish programs until schools enrolled in its service. In October 1963, the Kentucky Authority for Educational Television applied for the first construction permits to build the network after clarifying grant rules that initially seemed to make the state government ineligible for funding from the United States Department of Health, Education, and Welfare.

However, a two-year setback was experienced in 1964 when the General Assembly—which budgets on a biennial basis—refused to fund construction of the transmitters. Other state needs were prioritized: in education, these included issues in Jefferson County, low teacher pay, and transportation problems. Planning activities continued during the period. The Elizabethtown transmitter had been added to the proposed network by 1965, when a feature article in the Sunday Herald-Leader noted that Kentucky's plan for transmitter construction had been adopted by other states, notably Georgia. Schools, meanwhile, continued to depend on sources such as MPATI and commercial stations in bordering states, such as WSAZ-TV in Huntington, West Virginia. However, MPATI increased its fees, and WSAZ-TV dropped the mathematics program it was carrying due to scheduling difficulties, affecting 2,700 students in eastern Kentucky. Schools in south-central Kentucky continued to utilize educational programs from WDCN-TV in Nashville, Tennessee; Glasgow had been among the charter users of WDCN educational programming when it began in 1962, and Bowling Green followed suit in 1964.

The 1966 General Assembly budget provided the necessary funds to start work on building KET by including a $359,000 (equivalent to $3,479,170 in 2024) appropriation. Another impetus was given by the Stuart Blazer Foundation, set up by Ashland Oil founder Paul G. Blazer in memory of his deceased son. The foundation began buying and deeding transmitter sites to the state, beginning with the Somerset site in April 1966. Federal matching funds were applied for and received from the Department of Health, Education, and Welfare and the Appalachian Regional Commission, while the FCC granted the 12 construction permits later in the year. After awarding WCVN-TV in Covington in late September, the commission awarded the remaining construction permits in November, the largest single award of permits to one applicant in its history. Ground was broken on the Lexington production center in June 1967, followed by bids for the equipment needed at the studios and transmitters.

By May 1968, work on the Lexington and Somerset transmitters had been completed, and KET had announced its initial array of 19 in-school programs, mostly for elementary school students. However, site problems snarled work in Covington. Ashland Oil had provided property in the Taylor Mill area, though the city of Covington also provided sites. However, Taylor Mill met with citizen protest despite being approved by the city council, while sites in Covington would interfere with a new instrument landing system for the Greater Cincinnati Airport. As a result, KET opted to return to Taylor Mill, in spite of opposition whipped up by a local housewife who fretted the facility would be a hazard to aviation and generate interference to reception of other TV stations.

KET finally went on the air for the first time on September 23, 1968, at 7:30 a.m. Eastern Time (6:30 a.m. Central Time). The first broadcast started with Governor Louie B. Nunn speaking at the network's dedication ceremony; Nunn himself turned the dial to officially put the network on the air. That first day, eight transmitters opened, at Ashland, Bowling Green, Elizabethtown, Lexington, Madisonville, Morehead, Owenton, Somerset, plus two dependent translators at Hopkinsville and Owensboro. Initially unable to produce its own programs, the original set of courses broadcast by KET were leased or purchased from other producers. The initial broadcast was viewed by about 1,400 schools.