In light of the research problem, the research objective is as follows: 1- Measuring the direct relationship between financial statement amendments and the financial performance of joint stock companies listed on the Egyptian Stock Exchange. 2- Measuring the direct relationship between financial statement amendments and the cost of capital for joint stock companies listed on the Egyptian Stock Exchange. 3- Measuring the direct relationship between the cost of capital and the financial performance of joint stock companies listed on the Egyptian Stock Exchange. 4- Analysis of the mediating effect of the cost of capital in explaining the relationship between financial statement amendments and the financial performance of joint stock companies listed on the Egyptian Stock Exchange.