Abstract
The various countries seek to encourage their local investments through the various policies they follow. The most important of these is the monetary policy, which is a means and procedures taken by the monetary authority to control the supply of money and maintain its stability of its financial impact on economic activity.
The effect of monetary policy is to stimulate domestic investment through money supply that is inversely related to the interest rate and a direct relationship with domestic investment. When money supply increases, interest rates fall and local investment growth rates rise, but when the rise in money supply is high, Inflationary measures that negatively impact savings and investment. In this case, the monetary policy tools of compulsory reserve and the rate of rebate play a vital role in absorbing this excess liquidity. Thus, the most important variables for private investment in Algeria are Interest rate, money supply.