Prime Minister Manmohan Singh and Congress heavyweight A K Antony are also expected to reach the state for the campaigning.
CPM general secretary Prakash Karat will campaign for Left candidates on April 5 in Kochi and Alappuzha.
Prakash will attend public rallies in Pathanamthitta and Kollam on April 6.
On April 7, he is scheduled to attend election campaigns in Thiruvananthapuram and Attingal.
Sitaram Yechury, CPM politburo member, will be in the state for the election campaigns on April 3, 4, 5 and 6, and will be campaigning in Chalakkudy, Thrissur, Palakkad and Kozhikode.
S Sudhakar Reddy, CPI general secretary, will be in the state on April 2 and 3, and will be attending public rallies in Chalakkudy, Thrissur, Malappuram and Thiruvampadi.
Senior CPI leader A B Bardhan will be in the state on March 31 for Left campaigns in Attingal and Thiruvananthapuram.
A B Bardhan will be in Alappuzha and Kollam on April 1.
On April 2, Bardhan will campaign in Chalakkudy and Thrissur for campaigns.
Another CPI leader D Raja will also be campaigning for the party candidates in Idukki on April 4 and Palakkad on April 5.
Star Campaigners
UDF: Sonia Gandhi (April 7), Rahul Gandhi (April 4), A K Antony (March 30 onwards)
LDF: Prakash Karat (April 5, 6, 7), Sitaram Yechury (April 3, 4, 5, 6), S Sudhkar Reddy (April 2,3), A B Bardhan (March 31, April 1, 2)
BJP: Narendra Modi (April 4), Venkaiah Naidu (March 29, April 4).