Microsponges are tiny, uniform, micro-porous polymeric beads and spherical in shape. It has the interconnected voids. The particle size of it ranges between 5-300μm. The porous surface of non-collapsible structure of microsponges helps to deliver the active ingredient in controlled manner. Diclofenac Sodium is a Non-steroidal anti-inflammatory drug. The plasma half-life of Diclofenac is 1-2 hrs which increases the dosing frequency and this drug also causes the gastrointestinal irritation. Therefore the purpose of present investigation was to design suitable controlled release Diclofenac Sodium microsponges which can reduce the dosing frequency and gastric irritation. In the present work, Diclofenac Sodium loaded eudragit microsponges were prepared using quasi emulsion solvent diffusion method. Different drug: polymer ratios were used to formulate the microsponges. The compatibility of the drug with polymer was established. Surface morphology of the microsponges was examined using scanning electron microscopy. Production yield, loading efficiency, particle size analysis, and in-vitro release studies were carried out. In-vitro release study showed that the release of drug was in controlled manner and it was increased with increase in drug to polymer ratio up to certain limit.