The poor dissolution rate of water-insoluble drugs is still a major problem conforming the pharmaceutical industry. The most common method for improving the solubility is by increasing the surface area of the drug through micronization. But, in practice the effect of micronization is often disappointing, especially when the drugs are encapsulated or tablet. It is generally recognized that low solubility or dissolution rate often becomes a rate-limiting step in absorption of poorly water soluble drugs. Therefore, the enhancement of the dissolution rate of poorly water-soluble drugs after oral administration is one of the most challenging aspects of modern pharmaceutics. Olanzepine (2-methyl-4-(4-methyl-1-piperazinyl)-10H-thieno [2, b] [1, 5]benzodiazepine possess antipsychotic activity and exhibits very slight solubility in water and as a consequence it exhibit low bioavailability after oral administration Therefore, the improvement of olanzepine dissolution from its oral solid dosage forms is an important issue for enhancing its bioavailability and therapeutic efficacy. The purpose of present work is to improve the solubility of Olanzepine by preparing its dispersion with polymer PEG (Poly Ethylene Glycol) using solvent evaporation technique.