In this thesis, from poly ?-caprolactone which is a biodegradable polymer, nanofibers containing metronidazole benzoate were electrospun and evaluated for periodontal diseases. Solutions of 9.5%-11.5% w/v poly ?-caprolactone and 5%-15% w/w metronidazole benzoate in a mixture of dichloromethane and N,N-dimethylformamide with the ratios of 90/10, 80/20 and 70/30 were prepared, and the nanofibers were produced by electrospinning technique. Scanning electron microscopy (SEM) was used to investigate the effect of solvents ratios and polymer drug concentrations on the morphology and average diameter of the electrospun nanofibers. In order to study that no chemical interaction between polymer and drug has taken place, FTIR spectrums were evaluated. DSC results were also utilized to investigate the physical structure and probable chemical interaction of the polymer and drug. Drug release was studied in a phosphate buffer medium with pH 7.4. The amount of drug dissolved i this medium was determined by using the UV spectroscopy. Results showed that increasing DCM/DMF ratio will lead to a decrease in the solution conductivity and an increase in the solution viscosity as well as the nanofiber diameter. Also increasing the metronidazole benzoate concentration will lead to an increase in the solution conductivity and a decrease in the solution viscosity as well as the nanofiber diameter. The results showed that the drug release rate is affected by the solvents ratio as well as the polymer drug concentrations. In webs with appropriate thickness, the burst release was low and drug release was prolonged to 19-23 days. Metronidazole benzoate was released according to the fickian diffusion mechanism. Conclusively, poly ?-caprolactone electrospun nanofibers web can release metronidazole benzoate in a controlled manner, and drug loaded nanofibers can be used as a locally controlled delivery system for metronidazole benzoate in periodontal diseases