4-Aminosalicylic acid (4ASA) a non steroid anti inflammatory drug (NSAID) has been used for over 40 years in the treatment of inflammatory bowel diseases (IBDs). It is therefore an importance to assess physicochemical properties such as solubility and stability. The effect of cyclodextrins on the solubility and chemical stability of 4ASA was investigated. Inclusion complexes of 4ASA were characterized by the solubility method, differential scanning calorimetry (DSC) and Fourier transformer infrared spectroscopy (FT-IR). In addition, the influence of presence of CDs on stability was assessed at room temperature in different pH conditions. Complexation with CDs increased 4ASA aqueous solubility. The stoichiometric ratios of the inclusion complexes were 1:1 for α, β, γ and HP- CDs, respectively. Complexation with γ and HP-CDs has increased the 4ASA stability 4 fold. These observations suggest that 4ASA/CD complexes may be an attractive and practical procedure to modify drug physicochemical properties for use in delivery systems.