The influence of beta-tricalcium phosphate (ß-TCP) particles on the early cell attachment of MC3T3-E1 osteoblast precursor cells is investigated on a poly(3-hydroxybutyrate)/poly(3-hydroxybutyrate-co-4-hydroxybutyrate) polymer blend. MC3T3-E1 cells adhere to both polymer blends, with and without ß-TCP. In both cases, the cells show a typical cell morphology and focal adhesions on the polymer surface. The ß-TCP does not significantly improve the cell adhesion and hydrophilicity of the polymer films. Further, ß-TCP does not alter the degradation behavior of the poly(3-hydroxybutyrate)/poly(3-hydroxybutyrate-co-4-hydroxybutyrate) blend when exposed to phosphate buffered saline solution for up to 70 days. However, the results confirm that the polyhydroxyalkanoate blends used in this study are non-cytotoxic and maintain structural integrity over time. These findings highlight the blend's promise for usage in long-term biomedical applications, particularly in bone tissue engineering, because of their stability in isotonic medium.