Housing land supply is one of the most important issues that the planning discipline discusses from the several perspectives. On the one hand, population, local dynamics and economic policies that stimulate urban development have substantial impact on the size and form of the housing land supply, on the other hand, landowners and construction companies, who are aimed to get the highest benefits from housing construction, are powerful on directing both central and local governments land policies.This study aims to investigate this new housing land supply regime by focusing on institutional restructuring period and legal arrangements. In order to understand the structural reforms, and consequently, the role of central and local governments in housing land supply, new institutional economics (NIE) is applied as methodological approach.NIE focuses on institutions and formal rules in order to understand structural characteristics of the market and behaviour of market actors. In our case, the planning system to the extent of institutional structure and planning regime along with legal arrangements is structurally analysed in order to understand the current housing land supply regime. A comprehensive documentary analysis, including both institutional restructuring and legal arrangements, has been done to reflecting the structural changes in 2000s.Documentary analysis obviously reflects the dominant role of the state in new housing land supply regime. However, because of the inherent characteristics of the planning system and conflicts in power use of central and local governments, the conditions of perfect information and certainty in the land supply market is enable to create. Mutual relations is the other factor that disturb the housing land supply regime. Therefore, uncertainties in market conditions is high and actors behave in bounded rationality. Consequently, the new housing land supply regime is seen not be enable to create concreate market conditions to actors and not supported by consistent housing policies.