This paper develops an econometric model to examine the impact of land supply on residential housing prices. Specifically, this study examines the role of population, permanent income, real mortgage interest rates, construction cost, speculative demand, land supply and government land policy in the determination of private housing prices in Hong Kong. Empirical results provide strong evidence that an increase in land supply will bring forth a decrease in housing prices. The results also reveal that housing prices are dominated by the fundamental demographic and economic factors. The relatively small response coefficients suggest that speculative demand and land supply have a significant but modest impact on housing prices.