P. esculentus starch was chemically modified via carboxymethylation. The product was characterized using Scanning electron Microscopy (SEM), Fourier Transform Infrared (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopy. Physicochemical characteristics of the native and carboxymethyl starch such as Viscosity, solubility, Swelling power and viscosity-average molecular weight were also determined. The result showed that the starch from P. esculentus starch is composed of α −glucose linked together at 1→4. The carboxymethyl starch with degree of substitution 0.40±0.02 had higher physicochemical properties than the native starch. The result showed that chemical modification by carboxymethylation may improve the physicochemical properties of polysaccharides resulting in higher efficacy for effective utilization in starch-based industries.