Polyhydroxyalkanoates (PHAs) are emerging as the candidate of biodegradable material for the future, which in combination with nanoclay reinforcement can produce nanobiocomposites for a variety of applications. Thus, this project was intended to develop nanobiocomposites using various biodegradable PHAs: poly(3-hydroxybutyrate) [P(3HB)], poly(3-hydroxybutyrate-co-6 %3-hydroxyvalerate) [P(3HB-co-6 %3HV)] copolymer, poly(3-hydroxybutyrate-co-70 %4-hydroxybutyrate) [P(3HB-co-70 %4HB)] copolymer and poly(3-hydroxybutyrate-co-10 %3hydroxyvalerate- co-10 %4-hydroxybutyrate) [P(3HB-co-10 %3HV-co-10 %4HB)] terpolymer through solvent casting method. Pronounced improvement in the optical transparency, mechanical and thermal properties were achieved through reinforcement of 5 wt% Claytone into P(3HB-co-70 %4HB) having the lowest molecular weight as compared to the other polymers. P(3HB-co-70 %4HB)/5 wt% Claytone composite also exhibited enhancement in the antimicrobial performance which increased with the clay concentrations. P(3HB-co-70 %4HB), a biocompatible and biodegradable nanocomposite which had demonstrated salient features with comparable good performance is believed to create new prospects with special incidence in regenerative medicine and as environmentally friendly materials (green nanocomposites).