(GenBankAccession no. AM260479), was isolated from cassava starch wastewater of cassava starch manufacturingprocess. KKU38 can utilize glucose, fructose, maltose and xylose for PHA production. Glucose was the mostsuitable sugar for PHA production giving the highest PHA content and yield of 73.88% and 0.16 g/g-totalsugar consumed, respectively. Lactose and sucrose were not suitable carbon sources for both biomass andPHA productions. PHA production from cassava starch hydrolysate (CSH) by the strain KKU38 was maxi-mized under N-limited conditions (COD:N:P of 100:1:2.43). The moderately high biomass concentrationsof 5.97 g/L with PHA content and yield of 61.60% and 0.20 g/g-total sugar consumed, respectively, wereobtained under the optimum conditions. The analysis of PHA produced under the optimum conditions by1H NMR,13C NMR and FT-IR indicated that the produced polymer is homopolymer polyhydroxybutyrate(PHB).