Mohamed Aymen Ben Moussa, Chedia Hedfi
Firm size and profitability are important in the world of company. Profitability indicates the success and efficient use of resources by the firm. Also size is important because it indicate the importance of total assets; total sales or inventory. Large firms are more profitable in generally but in certain cases the small firms can access a large profitability by good management and efficient application of financial strategy. In this article we studied a sample of 30 firms quoted in Tunisian stock exchange for the period (2016-2021). We used a method of generalized least square (GLS). We found that size has a positive impact on both measure of profitability of firm (ROA and ROE).