Limestone has been used to be one of building materials since a very long time by people. It is used as a substitute material on concrete fine aggregate due to its particle's characteristics that is similar to sand. It is expected that by using additional material of natural limestone and mountain rocks as the substitute material will at least reduce the production cost of concrete in the places where limestone and mountain rocks are easily found. Therefore, a research related to the issue is necessary. This research aimed to find out the compressive strength of K-250 concrete (f'c : 20.7 Mpa) at 28 days. The variations of fine aggregate substitution were 10%, 20%, 30%, 40%, 50%, with 3 samples in each variation. The results showed that the compressive strength of concrete with aggregate substitution of 10%, 20%, 30%, 40%, 50% at 7 days were 20.63 Mpa, 8,52 Mpa, 7,27 Mpa, 5.54 Mpa, 8.44 Mpa, toward normal concrete 22.7 Mpa. Meanwhile, the conversions at 7 days were 22.07 Mpa, 9.12 Mpa, 7.78 Mpa, 5.93 Mpa, and 9.03 Mpa toward normal concrete 24.31 Mpa.