Niyamasabha Mandiram, Legislative building in Palayam, Thiruvananthapuram, India.

The Niyamasabha Mandiram is a five-storey legislative building in Palayam, Thiruvananthapuram, with a basement for official cars. Its main entrance faces west, and a 51-step staircase more than 200 feet wide leads to the foyer. The Central Assembly Hall rises 95 feet and has teak and rosewood panelling, 140 seats, and a dome built in traditional Kerala Koothambalam style.

The complex was established in 1979 after the previous legislative space became insufficient for growing needs. President Neelam Sanjeeva Reddy laid the foundation stone for this new site at Palayam.

The dome follows the traditional Kerala Koothambalam style, and the main entrance, 16 metres high, opens only for ceremonial occasions such as a visit by the Governor. The South Garden holds memorials to past leaders and veteran legislators, while the North Garden has water features. A statue of Mahatma Gandhi in a meditating pose stands in front of the grand staircase.

The main entrance faces west, and the 51-step staircase leading to the foyer is over 200 feet wide. The Central Assembly Hall has 140 seats and eight galleries for 800 people. The complex includes a basement parking area for 400 cars.

The complex stands on the Government Estate at Palayam, once the headquarters of the Nair Brigade of the Travancore army. The old Army Headquarters building was converted into the Legislature Museum, so the site's military past survives in a museum beside the new assembly.