The study examined the effectiveness of monetary policy in controlling inflation in Nigeria. In the model specified, inflation is the regress and while cash reserved requirement, liquidity ratio, money supply, minimum rediscount rate and interest rate are the regressor. Data was collected from CBN statistical Bulletin . The statistical techniques used for the analysis is the ordinary least square technical with the aid of E-view 5.0 software package. The research indicates that monetary policy adopted in Nigeria within the period under review failed to influence the inflation rate. It has been identified that the major problem militating against the poor performance of monetary policy instrument in controlling inflation in Nigeria is time lags involved which makes any policy employed to take many months to achieve its full effect.