Achuthanandan (87) filed his papers before returning officer A N Pradeepraj. He was accompanied by former Lok Sabha member N N Krishnadas and local party functionaries.
The Marxist stalwart is seeking election from Malampuzha for the third consecutive time. The segment had always been loyal to the CPI(M) and those who were elected to the Assembly from there included former chief minister late E K Nayanar.
Achuthanandan, who is the pivot of the LDF, has been campaigning in the northern districts for the last three days.
Congress has chosen 46-year-old woman leader Lathika Subhash, a debutant in electoral arena, to take on Achuthanandan.
The CPI(M) state unit initially decided not to field Achuthanandan in the elections but reversed it after widespread protests from party rank and file.
The u-turn, a replay of the 2006 scenario, came after the central leadership directed the state unit to revoke its decision, factoring in widespread protests, particularly from party leaders and cadre.