The aim of this study was to prepare and evaluate ethyl cellulose floating microspheres containing Ranitidine hydrochloride. Microspheres were prepared by non-aqueous solvent evaporation method using ethanol/ liquid paraffin system. The influence of formulation factors (drug: polymer, stirring speed, concentration of surfactant) on particle size, encapsulation efficiency and in vitro release characteristics of the microspheres were investigated. The yields of preparation and encapsulation efficiencies were high for all formulations obtained. Mean particle size changed by changing the drug: polymer ratio or stirring speed of the system. Although Ranitidine hydrochloride release rates from ethyl cellulose microspheres were decreased as the concentration of ethyl cellulose increased. By applying one way ANOVA followed by Newman-Keuls Multiple Comparison value obtained (p< 0.05) was considered to be statistically significant.