The focus of this research work is based on the impact of interest rate policy on investment in the Nigerian economy between the period of 1981 – 2009. because interest rate and investment is at core of economic stabilization. The objective of this study is to examine the impact of interest rate policy onNigeriaprior to interest rate regulation in 1987 and to serve as a guide on how interest rate can be fixed to enhance effective accumulation of savings that can be channeled to investment. The study employed the ordinary least square technique which also employ. Secondary data obtained from the central bank of Nigeria (CBN) statistical bulletin. The main findings revealed that there is a negative relationship between interest rate and investment and also there is a significant relationship between savings and interest and finally, recommendations were made on how interest rate can be performed optimally.