The Congress leaders, including Rahul Gandhi, Defence Minister A K Antony and Delhi Chief Minister Sheila Dixit placed wreaths on Reddy's body at the chief minister's camp office in Begumpet area in Hyderabad.
The leaders also wrote condolence messages at the camp office. The leaders arrived in Hyderabad early morning by a special flight.
Home Minister P Chidambaram and other union ministers, including Sushil Kumar Shinde, Salman Khurshid and Andhra Pradesh Governor N D Tiwari were among others who offered their tributes and placed wreaths on Reddy's body.
The leaders consoled the family members including the late chief minister's son Y S Jagan Mohan Reddy.
Thousands of party workers, who came in from different parts of the state, also paid homage to their departed leader throughout the night.