Money supply is one of various important factors for the development of a country, because the varying of money supply will affect to a number of macroeconomic variables, such as gross domestic product, interest rate , invesment, consumption and price level. Thus the government should control money supply in the appropriate level. The objectives of this study are to study factors that have impact on money supply that circulate in the Thai Economy and to find the relationship between price level and money supply as well as other factors such as import price level, wage and price level in the previous year. The study used annually secondary data from the period 1967-1989. A descriptive analysis prescribed the trend of money supply and price level whereas multiple equations are used to analyse factors afffecting money supply and also find the relationship between price level and money supply as well as other factors. The result of the analysis indicated that the factors that have impact on money supply both narrow and broader definition are private sector credit, net government sector credit and net foriegn asset. On th other hand the factor that influenced price level are price level in the previous year, import price level, wage and money supply in the narrow defintion. The conclusion of this study suggested that monetary policy could be used to control price level by varying the growth rate of money supply and controlling private sector credit of commercial bank.