The inter-relation of rain drop size distribution with cloud base height has been investigated at a tropical location, Kolkata (22°34′N, 88°22′E). The study focuses the association of rain drop size distribution with cloud base height during the summer monsoon and pre-monsoon. It is observed that the mean diameter of the largest drop increases with the lowering of cloud base height. A notable difference between the pre-monsoon and monsoon rain events have been identified in the inter-relation of rain drop size with cloud base height. Results indicate that the large drops are more frequent in the pre-monsoon season than the monsoon.