The objective of this study was to investigate the effect of interest rate on investment and liquidity in the Tehran Stock Exchange companies. For that purpose, first, a review of the literature on the subject of research is provided and then the variables concerned in the research are described and its theoretical foundations are briefly outlined in which the interest rate is known as an independent variable and investment and liquidity are regarded as associated variables. In this research, the statistical population includes all the companies listed at the Tehran Stock Exchange among which a sample of 160 companies were selected from the statistical community for the period of 5-150 years (2011-2015) after the screening method, and the sample size, according to the filtration rule, involved and studied 800 years companies. The data were collected using Rahavard Novin software, EViews was also used for descriptive analysis of data, hypothesis testing and regression model extraction. The research methodology is practical in terms of its objective, descriptive in terms of its implementation, and of correlation type. The findings of this research indicate that there is a negative relationship between the interest rate and investment and there is a direct relationship between the interest rate and liquidity in the companies listed at the Tehran Stock Exchangey.
