To investigate the effectiveness of Kigelia africana methanolic extract on the inhibition of crystallization in synthetic urine, calcium oxalate (COM) and sodium oxalate solutions were induced together to form crystallization as synthetic urine. Methanolic extract of Kigelia africana was prepared in four different concentrations (25, 50, 75, 100μg/ml). An analysis was done to verify the turbidity changes during the crystal nucleation and the aggregation in the solution of synthetic urine was observed at 620nm by spectrophotometer and standard was used as a cystone. Methanolic extract was tested against the artificial stone of calcium oxalate crystals by homogeneous precipitation method. This study was assessed for a crystal dissolution using the semi-permeable membrane of the egg which is used as dissolution bag and the estimation was done using a spectrophotometric method. The result shows that extract of Kigelia africana has greater capability to dissolve the calcium oxalate compared to the standard of cystone that shows better activity in dissolution model. Kigelia africana extract and cystone exhibited strong inhibitory activity in the nucleation and aggregation assays. We concluded that Kigelia africana leaf extract remarkably inhibits the crystal formation and it has good potential for the antiurolithiatic activity. Hence, further investigation and formation of new drugs from this medicinal plant can be used for urolithiasis. © 2018 World Research Association. All rights reserved.