Carica papaya is known to influence the growth of plants in its vicinity by the release of the allelochemicals during the decomposition of its litter. The purpose of this study is to assess the allelopathic effects of Carica papaya aqueous leaf extraction seedgermination characteristics, primary growth and biochemical changes associated with Phaseolus aureus. For the study, C papaya aqueous leaf extract of dry mature leaves of concentrations viz., 0. 1%, 0.2%, 0.3%, 0.4% and0.5% were made, while tap water served as control. Green gram seeds were incubated in different concentrations of leaf extracts and germination data was recorded.After 15th, 30th&45th days of exposure to the extract, seedlings were harvested and measurements for root and shoot length, fresh weights of root, shoot, and seed was taken and biochemical characteristics such as carbohydrates, protein, chlorophyll, proline and phenol content of the seedlings wereassayed. Germination and phenotypic results showed no negative affect by the extractin T1, T2, T3 treatments. The amount of total carbohydrate, chlorophyll and protein content were found to be stimulated in T3. Lower concentration (T3) which appear to be suitable to green gram, showed a decrease in stress preventing compounds such as total phenol and free proline. Optimum and healthy growth were observed in T3 treatment. The results indicate the possible application of C.papaya aqueous leaf extract for growth improvement without pest attackof P. aureus.