Japanese oysters are rich in nutritional value and contain the fundamental flavor compounds desired in the oyster sauce, while green mussels and clams offer nutritional equivalence and lower cost. In Cambodia, a market analysis presently indicates a lack of commercial oyster sauce incorporating with green mussels and clams. Therefore, this study aimed to develop the oyster sauce produced from Japanese oysters, green mussels, and clams. Four different conditions of oyster sauce were developed such as 100% Japanese oysters (JO), 100% green mussels (GM), 100% clams (Cl), and a mixture of 30% Japanese oysters; 50% of green mussels and 20% clams (JGC). The physicochemical properties of oyster sauce including moisture content, pH, total acidity, total soluble solids, salt content, water activity, consistency were determined. Moreover, the microbiological characteristics (total plate count, yeast and mold count, total coliforms, Staphylococcus aureus, Salmonella), and the sensory attributes were also evaluated. The results showed that the raw materials did not impact significantly the moisture content of oyster sauce (p > 0.05), which ranged from 53.52-60.33%. However, the results of pH, total soluble solids, salt content, total acidity, consistency and water activity were significantly were affected (p < 0.05) by the raw materials, varying between 5.65-5.79, 45.77-50.10Brix, 1.05-1.72%, 0.78-1.24%, 11.33-23 cm/min, and 0.88-0.93, respectively. There were non-detected of microbial count in JGC sample; however, the total plate count, yeast and mold, and S. aureus were found in JO, GM, and Cl samples. Among all conditions, JGC sample provided the highest sensory score (6.75) of overall acceptability. For future study, the nutritional profile and shelf-life observation of oyster sauce made from a mixture of Japanese oysters, green mussels, and clams should be further investigated.