Polyhydroxyalkanoate (PHA) is a cellular storage polymer with similar properties to some plastics when extracted from the cell and acts as a renewable and biodegradable plastic alternative. The objective of this research was to identify thermophilic PHA producing microorganisms and characterize their PHA accumulation, by which the process may become more competitive to current petroleum-based plastic production. This study characterizes growth and PHA production of Thermus thermophilus HB8 and three strains of T. filiformis (MOK, NGM and WRT), while simultaneously performing a genetic analysis for the presence of a phaC gene that encodes the PHA synthase. The results from the genetic analyses, together with attempts to produce PHA in T. thermophilus HB8 and T. filiformis strain (WRT, NGM and MOK) infer an absence of PHA accumulation. Contrary to our expectations, Thermus sp. is not a strong candidate for the thermophilic production of PHA.