Along with Chandy, P K Kunhalikutty (IUML), K M Mani (KC-M), K P Mohan (SJD), T M Jacob (KC-J), K B Ganesh Kumar (KC-B) and Shibu Baby John (RSP-B), partners of the United Democratic Front, will also be sworn in at 2 pm.
They will be administered oath of office and secrecy by Governor R S Gavai at a ceremony to be held at the Raj Bhavan lawns, UDF sources said.
The Ministry will be expanded later after finalising the list of Congress members to be included in consultation with the party's central leadership.
UDF captured power in the state pipping the Left Democratic Front by a margin of 72-68 in the 140-member Assembly in a photo-finish in the April 13 elections.
Chandy, who was on Sunday elected leader of the Congress Legislature Party, said the front partners have already reached a broad agreement on the number of berths to be shared through discussions in the last two days.
According to the consensus, the second largest UDF component IUML would get four cabinet berths and Kerala Congress (M) two, though the latter continues to press for three. Other partners get one portfolio each.
Apart from the Chief Minister, Congress is trying to ensure ten ministerial berths for itself so as to satisfy its diverse support base by maintaining proper regional, caste and religious balance.
Chandy and KPCC president Ramesh Chennithala would be leaving for Delhi on Thursday to finalise the party's list.
As the lead partner, Congress has made it clear that it would keep the Assembly Speaker's post, which is crucial since the coalition commands only a slender majority in the House.
However, the post of Deputy Speaker would be left to either IUML or the Kerala Congress (M).