Members of assembly will cast their votes here till 5 pm while four members of Parliament from have also sought permission to vote in Hyderabad.
The ruling Congress party has 155 members in the 294-member assembly.
Defying Telugu Desam Party's diktat, five legislators of the party also turned up at the assembly to exercise the franchise. The TDP, which has 85 members in the assembly, has decided to abstain from voting.
Telangana Rashtra Samithi (TRS), which has two MPs and 17 MLAs, has decided to abstain and so has the Communist Party of India (CPI).
Jailed YSR Congress Party MP YS Jaganmohan Reddy and former state minister and Congress legislator Mopidevi Venkatramna will also cast their vote. They are currently lodged at the Chanchalguda Jail here in the case relating to Jaganmohan Reddy's disproportionate assets. A special court has permitted both the leaders to vote in the presidential election.
The YSR Congress, which has two MPs and 17 members of assembly, has already its declared support for United Progressive Alliance (UPA) candidate Pranab Mukherjee. Against him is former Lok Sabha speaker PA Sangma, who is being backed by the BJP, the AIADMK and BJD.
The Majlis-e-Ittehadul Muslimeen, which has one MP and seven MLAs, will be voting for Mukherjee. The CPI-M and Lok Satta, which have a legislator each, have also declared support to Mukherjee.