The size-frequency-disitribution method was used to study the rate of growth in Donax cuneatus- It was found that Donax grew to a size of 13-14 mm, 21-22 mm and 22-23 mm, respectively within one year, two years and two- and-half years. The relationships between length and breadth, and length and width have been found to be of a linear type and length-weight relationship followed a cube law. Sexual maturity was attained in this clam at the size of 13 mm when they were eleven months old. A single spawning from October to January was observed during a year. The rate of growth was not uniform throughout the year. There was a moderate growth from December to January, a rapid growth from February to June and poor growth from July to November. Rising salinity during the period from February to June accelerated the growth while low salinity during monsoon and winter seemed to retard the growth