Levomilnacipran is used as an antidepressant and Levo enantiomer of Milnacipran which is used for the treatment of fibromyalgia. The RP-HPLC method was developed by using Symmetry C-18, 150*4.6mm, 3.5µm column with mobile phase A of Buffer which is made up of orthophosphoric acid and mobile phase B was made up of water, and acetonitrile in the ratio of 90: 10% v/v. The diluent taken was water and methanol in the ratio of 50:50% v/v. Flow rate was 1.0µL/min, UV detection at 210nm with PDA detector and the injection volume was 10 µL and the run time was 50mins. This method was validated with respect to Phthalimido impurity for specificity and found no interference of any other substances. Linearity studies were done for phthalimido impurity from 0.47ppm to 3.15ppm and found correlation coefficient as 0.998. Precision was performed and found %RSD as 0.7. Accuracy was also performed from 50% to 150% and recovery found above 92%. Robustness and ruggedness were found in limits. The linearity of Levomilnacipran was found from 9.6µg/ml to 22.4µg/ml. Accuracy for Phthalimido impurity was performed from 50% to 150% and recovery was found to be in limits. Degradation studies were performed to know the amount of drug degraded during acid, base, peroxide, humidity, thermal and photolytic stresses. It was found that the drug was degraded more in peroxide stress