The Polyhydroxyalkanoates (PHAs) are intracellular polyesters synthesized by different bacterial species. PHAs are accumulated as granules when bacterias don´t find conditions for their growth, like oxygen and essential nutrients (nitrogen, carbon). PHA is biodegradable and depending on its chemical and structural composition can be used in similar applications to polymers [1]. At present this type of biopolymers have a higher cost compared to petroleum, but the use of renewable sources friendly to the environment or the use of agro-products for generating new products is a practice of global importance. The present investigation studied the production of polyhydroxyalkanoates (PHA) by bacterial fermentation of glucose obtained from HMC1 cassava flour using Ralstonia eutropha, using five different ratios carbon/nitrogen (12:1, 16:1, 20:1, 24:1, 28:1). The result showed the carbon/nitrogen ratio of 20 is the most favorable to the intracellular accumulation of biopolymer, with which a production of 0,62 g/L of PHA. The PHA was characterized PHA by differential scanning calorimetry (DSC), thermogravimetric Analysis (TGA), Infrared Spectroscopy with Fourier Transform (FT-IR) and scanning electron microscopy, obteining as conclusion that the polymer synthesized was polyhydroxybutyrate (PHB).