Tropical cyclones (TCs) cause tremendous loss of properties and life through their gusty winds and slashing rain. Better precipitation estimations and modeling simulations of TCs can be achieved through an enhanced understanding of the microphysical properties, particularly the raindrop size distributions of the TCs. This chapter documents raindrop size distributions of Indo-Pacific tropical cyclones measured at three locations using two types of disdrometers. The differences in the raindrop size distributions (RSDs) between the Indian and Pacific Ocean tropical cyclones and their possible rationale are detailed. Also, the dissimilarities of the north Indian Ocean (NIO) TCs measured at the coastal and inland stations and their possible microphysical attributes are documented. Furthermore, the RSDs of Western Pacific (WP) TCs measured at an Oceanic station in the WP are also detailed. The raindrop size distribution and rainfall kinetic energy relations that are handy in the rain retrieval algorithm of ground-based/remote sensing radar and rainfall erosivity studies are also reported in this chapter.