Abstrak Penelitian ini bertujuan untuk mendapatkan komposisi agregat kasar gabungan Batu Banjarmasin dan Batu Merak dengan tambahan superplasticizer yang memberikan kuat tekan optimum. Untuk mencapai tujuan tersebut dilakukan penelitian di laboratorium menggunakan benda uji silinder dengan diameter 150 mm dan tinggi 300 mm. Terdapat 2 jenis campuran yaitu campuran beton tanpa superplasticizer dan campuran beton dengan tambahan superplasticizer. Masing-masing campuran tersebut terdiri dari 4 variasi campuran. Berdasarkan hasil pengujian beton tanpa superplasticizer kuat tekan optimum dicapai pada campuran dengan prosentase 50% Batu Banjarmasin-50% Batu Merak sebesar 27,10 MPa. Kuat tekan beton dengan proporsi campuran 60% Batu Banjarmasin-40% Batu Merak, 70% Batu Banjarmasin-30% Batu Merak, 80% Batu Banjarmasin-20% Batu Merak berturut-turut 24,61 MPa; 22,09 MPa dan 19,29 MPa. Kuat tekan optimum beton dengan tambahan superplasticizer dicapai pada campuran dengan prosentase 50% Batu Banjarmasin-50% Batu Merak sebesar 37,18 MPa. Kuat tekan beton dengan proporsi campuran 60% Batu Banjarmasin-40% Batu Merak, 70% Batu Banjarmasin-30% Batu Merak, 80% Batu Banjarmasin-20% Batu Merak berturut-turut 31,51 MPa; 24,25 MPa dan 25,34 MPa. Campuran beton dengan tambahan superplasticizer memberikan hasil kuat tekan yang lebih besar dibanding campuran beton tanpa superplasticizer. Kata kunci: Sifat fisik agregat, agregat kasar, kuat tekan, superplasticizer Abstract This study aims to obtain the composition of the combined coarse aggregate of Banjarmasin Stone and Merak Stone with the addition of superplasticizer which provides optimum compressive strength. To achieve this goal, research was carried out in the laboratory using cylindrical specimens with a diameter of 150 mm and a height of 300 mm. There are 2 types of mixtures, namely concrete mixtures without superplasticizers and concrete mixtures with the addition of superplasticizers. Each of these mixtures consists of 4 variations of the mixture. Based on the test results of concrete without superplasticizer, the optimum compressive strength was achieved in a mixture with a percentage of 50% Banjarmasin Stone-50% Merak Stone of 27.10 MPa. The compressive strength of concrete with a mixture proportion of 60% Banjarmasin Stone-40% Merak Stone, 70% Banjarmasin Stone-30% Merak Stone, 80% Banjarmasin Stone-20% Merak Stone respectively 24.61 MPa; 22.09 MPa and 19.29 MPa. The optimum compressive strength of concrete with the addition of superplasticizer was achieved in a mixture with a percentage of 50% Banjarmasin Stone-50% Merak Stone of 37.18 MPa. The compressive strength of concrete with a mixture proportion of 60% Banjarmasin Stone-40% Merak Stone, 70% Banjarmasin Stone-30% Merak Stone, 80% Banjarmasin Stone-20% Merak Stone respectively 31.51 MPa; 24.25 MPa and 25.34 MPa. Concrete mixes with the addition of superplasticizers give greater compressive strength results than concrete mixes without superplasticizers. Keywords: aggregate physical properties, coarse aggregate, compressive strenght, superplasticizer