KBUE (105.5 FM, "Que Buena 105.5/94.3 FM") is a commercial radio station licensed to Long Beach, California, that serves the Los Angeles metropolitan area. It is owned by Estrella Media and airs a Regional Mexican radio format. Studios and offices are on Hollywood Boulevard in Los Angeles.

KBUE's transmitter is located off East University Drive in Rancho Dominguez, California. It has an effective radiated power of 3,000 watts, making it a Class A station. (Most other major Los Angeles area stations have more powerful Class B signals with their towers high up on Mount Wilson.) To fill in gaps in KBUE's coverage area, "Que Buena" is also simulcasted on co-owned and co-channel 94.3 KBUA in San Fernando and KEBN in Garden Grove.

A Federal Communications Commission construction permit for 105.5 FM in Beverly Hills was issued to Saul Levine in May 1957 as KBCA. The construction permit was sold the next year to Long Beach FM Broadcasting Company, which moved the proposed facility to Long Beach. It was sold the next year to Harriscope Music Corporation, owned by Bert Harris, and made its debut January 1, 1961, as KLFM. However, Levine did not get the station built, even though he would go on to own KKGO and other California stations. Finally, on New Year's Day 1961, KLFM signed on the air. It was owned by the Harriscope Music Corporation, with Bert Harris serving as president and general manager. The station was initially powered at only 330 watts, keeping its signal restricted to Long Beach and adjacent communities. KLFM's studios were initially located in a trailer adjacent to its transmitter on Signal Hill, moving to Lakewood Center and then to 4406 Greenmeadow Road. KLFM played Top 40 hits in an era where most young people used AM radios to hear their music. In the 1960s, most FM stations simply simulcast their co-owned AM stations, or played easy listening or classical music, often using broadcast automation.

Harriscope sold KLFM in 1966 to the McCray Broadcasting Company, headed by W. Mike McCray, Carl C. Loucks, and Robert Switzer. McCray changed the call sign to KNAC and instituted a full-time Middle of the Road (MOR) format, but the station went silent from March through August 1967. That year, the International Cities Broadcasting Corporation bought KNAC and increased its power to 2,100 watts. Additionally, KNAC relocated to the International Tower in downtown Long Beach.

In late 1967, the station began programming progressive rock from 6 p.m. to 6 a.m. The programming proved successful enough to make the rock format full time by 1969 when Harden Broadcasting bought KNAC. Air talent at KNAC during this era included Jim Ladd (later of KLOS), Jerry Longden (later of KROQ), and Program Director Ron McCoy. Ladd left KNAC to work for KLOS in 1971 while McCoy stayed on through much of the 1970s. The station stayed with progressive rock until 1980 when it made a significant adjustment in its rock format.

In 1980, the station adopted one of the first full-time commercial alternative rock formats in the country. Up to that point, Pasadena-based KROQ-FM and stations in Phoenix, Seattle, and New York City had attempted such formats. KROQ notwithstanding, most commercial attempts at alternative rock were short-lived. KNAC began using the slogan "Rock and Rhythm" and programmed a mix of "new wave", techno, punk, and some classic rock from the 1950s and 1960s. The station gathered media attention, but it was dwarfed by KROQ-FM's stellar ratings and Rick Carroll-consulted "Rock of the 80s" Alternative format. In late 1985, KNAC was acquired by Fred Sands, a Los Angeles-based realtor.

On January 8, 1986, the station flipped to a "Hard Rock/Heavy Metal music" format, the first of its kind on a commercial station in the United States. Several air staff members of the heavy metal station eventually went on to the original satellite-distributed, nationally syndicated "Z Rock" format in September 1986. KNAC played a wide variety of heavy metal and rock-based music from the late-1960s to 1995, the radio station's last year on the air, including classic rock, hard rock, traditional heavy metal, progressive rock/metal, power metal, glam metal, thrash metal, crossover thrash, death metal, groove metal, alternative metal, and grunge. KNAC was also responsible for helping launch the careers of previously low-key metal and hard rock bands, and is often credited for being the first radio station to promote new bands before their large-scale success, including Metallica, Guns N' Roses, Bon Jovi, Megadeth, Skid Row, Metal Church, Pantera, Alice in Chains, Soundgarden, Stone Temple Pilots, White Zombie, Poison, Testament, Stryper, Lizzy Borden, and Armored Saint. However, revenues were not what management had hoped for. While much of KNAC's core-base of artists were considered mainstream, the station played enough "cutting edge" artists of the day and acquired a legend that survived long beyond its demise in spring 1995. The station inspired tribute pages and an Internet radio station.

In 1995, Liberman Broadcasting, a Spanish-language broadcasting company, bought KNAC for $13 million. On February 15th of that year, after playing "Fade to Black" by Metallica, KNAC signed off for the last time. Three weeks later, on March 6th, the Spanish format launched with "Guadalajara" by Mariachi Sol de México being the first song played. The station would switch to the KBUE calls the same day. The format was "Ranchera-Mexican style" according to program director Fidel Fausto. The new call letters and format did not change the fact that KBUE's signal only covered southern Los Angeles County and northwestern Orange County. Liberman would buy additional radio stations to increase the coverage of the Que Buena format.