This research aimed to study and test the Relationship between Tax Avoidance and Cost of Capital for the Egyptian listed companies, using a sample of (106) non-financial companies listed on the Egyptian Stock Exchange belonging to (14) economic sectors, with a total of (494) observations during the period from 2016 to 2020, relied on a multiple linear regression model to test the hypothesis of the study, based on the dependent variable: (Cost of Capital) Measured by the weighted average cost of capital is a function of each of [(the independent variable: Tax avoidance level measured by the difference between the legal tax rate “22.5%” and the effective tax rate), and (control variables: Firm size, Rate of return on assets, Leverage, Operating cash flow ratio, Growth opportunities)]. The results of this research find: A negative, statistically significant relationship between tax avoidance and the cost of capital, which means (acceptance of the research hypothesis), and find: A negative, statistically significant relationship between Firm size and the cost of capital, A positive statistically significant relationship between (Rate of return on assets, Leverage, Growth opportunities) and the cost of capital, and there is no significant relationship between operating cash flows and the cost of capital