The Left Democratic Front (LDF) is an alliance of left-wing political parties in the state of Kerala, India. It is the current ruling political alliance of Kerala, since 2016. It is one of the two major political alliances in Kerala, the other being Indian National Congress-led United Democratic Front, each of which has been in power alternately for the last four decades. LDF has won the elections to the State Legislature of Kerala in the years 1980, 1987, 1996, 2006, 2016 and had a historic re-election in 2021 where an incumbent government was re-elected for first time in 40 years. LDF has won 6 out of 10 elections since the formation of the alliance in 1980. The alliance consists of CPI(M), CPI and various smaller parties.

The elections to the Eighth Kerala Assembly were held on March 23, 1987. The UDF and the LDF were the two major political fronts in the arena. The UDF had the INC(I), IUML, KC(J), KC(M), NDP (P), SRP(S) and the RSP(S) as its constituents. The LDF consisted of the CPI(M), CPI, RSP, IC(S), Janata Party and the Lok Dal.