Biodegradable polymeric micelles have potential therapeutic applications; nevertheless, preparing micelles of a specific diameter and uniform size distribution is a challenge. Micelles were formed from the copolymer of poly(epsilon-caprolactone)-poly(ethylene glycol)-poly(epsilon-caprolactone) and the effect of PCEC molecular weight, PCL/PEG ratio, solvent-water miscibility, solvent concentration on particle size, polydispersity index and zeta potential of micelles were also investigated. The average particle sizes of the PCEC micelles ranged between 225-959 and 232-1211 nm for micelles prepared with acetone and dimethylformamide, respectively. The encapsulation efficiency is 78.98%. These results indicate that PCEC micelles can be used as drug carriers in controlled delivery systems.