The study used the quantitative descriptive research design. The research population comprised all the stocks listed in the IDX30 index published biannually with a total of 30 stocks. The variables in the study were stock return, market return, stock risk, and market risk. The calculation of the expected return used the capital asset pricing model.The results of the study to find out the optimal portfolio of stocks by using capital asset pricing model were as follows. (1) The stock that made up the optimal portfolio were those of (1 adalah TBIG ( Tower Bersama Infrastructure Tbk.), MDKA (Merdeka Copper Gold Tbk.) dan UNTR ( United Tractor Tbk )  2) The composition of the proportion of funds formed by using the Composite Stock Price Index as the market return proxy was  allocated for the stocks of, 23% allocated for the stocks of TBIG ( Tower Bersama Infrastructure Tbk.)  , 45%, allocated for the stocks of) MDKA (Merdeka Copper Gold Tbk.), 32%. allocated for the stocks of UNTR ( United Tractor Tbk ).