The lieutenant governor of Indiana is a constitutional office in the US state of Indiana. Republican Micah Beckwith, who assumed office January 13, 2025, is the incumbent. The office holder's constitutional roles are to serve as the president of the Indiana Senate, become acting governor during the incapacity of the governor, and become governor should the incumbent governor resign, die in office, or be impeached and removed from office. Lieutenant governors have succeeded ten governors following their deaths or resignations. The lieutenant governor holds statutory positions, serving as the head of the state agricultural and rural affairs bureaus, and as the chairman of several state committees.

The lieutenant governor is elected on the same election ticket as the governor in a statewide election held every four years, concurrent with United States presidential elections. Should a lieutenant governor die while in office, resign, or succeed to the governorship, the constitution specifies no mechanism by which to fill vacancies in the lieutenant governor's office. Historically, the position has generally remained vacant during such events. The last attempt to fill such a vacancy in 1887 led to the outbreak of violence in the state legislature known as the Black Day of the General Assembly. However, in recent years the governor has appointed a lieutenant governor if a vacancy arises.

The position of lieutenant governor was created with the adoption of the first Constitution of Indiana in August 1816. The position was filled by an October election. The position was retained and the current requirements established in the state's second and current constitution adopted in 1851.

To become lieutenant governor, a candidate must have been a United States citizen and lived within Indiana for the period of five consecutive years before the election. The candidate must also be at least thirty years old when sworn into office. The lieutenant governor may not hold any federal office during his term, and must resign from any such position before being eligible to be sworn in as lieutenant governor. Before taking the office, the candidate must swear an oath of office administered by the chief justice of the Indiana Supreme Court, promising to uphold the constitution and laws of Indiana.

The lieutenant governor serves as acting governor when the governor becomes incapacitated. In the state's early history, lieutenant governors would serve as acting governor while the governor was away from the capital. Christopher Harrison was the first lieutenant governor to serve as acting governor while Jonathan Jennings negotiated treaties far from the capital.

If the governor dies in office, becomes permanently incapacitated, resigns, or is impeached, the lieutenant governor becomes governor. In total, ten lieutenant governors become governor by succession. The first occurrence was when Jonathan Jennings resigned to become a congressman and was succeeded by Ratliff Boon.

In the event that both the governorship and lieutenant-governorship are vacant, the constitution stipulates that the Senate president pro tempore becomes governor. Historically, governors appointed the pro tempore to serve as acting lieutenant governor as a formality. This practice ended in the early twentieth century. Although the constitution did not specify a method to fill a vacancy in the lieutenant governorship, an attempt to fill a vacancy occurred in 1887. When the winner of the election attempted to be seated, the Senate erupted into violence known as the Black Day of the General Assembly; the lieutenant governor-elect was sworn in but never seated.

Should the lieutenant governorship become vacant for any reason, including death, resignation, or succession, the governor may nominate a replacement who must be approved by both houses of the General Assembly.