PHAs (polyhydroxyalkanoates) have emerged as biodegradable plastics more strongly in the 20th century. A wide range of bacterial species along with fungi, plants, oilseed crops and carbon sources have been used extensively to synthesize PHA on large scales. Alteration of PHA monomers in their structures and composition has led to the development of biodegradable and biocompatible polymers with highly specific mechanical properties. This leads to the incorporation of PHA in numerous biomedical applications within the previous decade. PHAs have been fabricated in various forms to perform tissue engineering to repair liver, bone, cartilage, heart tissues, cardiovascular tissues, bone marrow, and to act as drug delivery system and nerve conduits. A large number of animal trials have been carried out to assess the biomedical properties of PHA monomers, which also confirms the high compatibility of PHA family for this field. This review summarizes the synthesis of PHA from different sources, and biosynthetic pathways and biomedical applications of biosynthesized polyhydroxyalkanoates.