In making stock investment decisions, it is important for investors to perform certain calculations and analyzes in order to be able to assess how well the performance of the issuer (company), with the aim of getting the expected rate of return and being able to minimize investment risk. This study was conducted to find out how the decisions that will be made by investors on buying shares on the Indonesia Stock Exchange using fundamental analysis. The difference between this study and previous research is that it adds a Positive Ideal Solution (PIS) and a Negative Ideal Solution (NIS) from financial information indicators ( Dept to Equity Ratio, Return on Equity, Net Profit Margin, Return On Assets, Earning Per Share, Price Earning Ratio). , and Price Book Value ) using the TOPSIS method. The sample in this study uses securities listed on the Indonesia Stock Exchange as many as 94 securities. The results showed that the Dept to Equity Ratio, Return On Assets, Earning Per Share, Price Earning Ratio, and Price Book Value had a significant effect on stock purchase decisions, while Return on Equity and Net Profit Margin had no effect on stock purchase decisions.