Allelopathic compounds are secondary metabolites created biologically by plants and microbes from the metabolism of carbohydrate, fats and amino acids. The process of their synthesis is affected by the type of plants, the path of its photosynthesis, its nutrition and various stress processes. When released to the rhizosphere, its effect begins on soil organisms, as it is considered a from of communication between plants. Which affects biological and agricultural systemis. A randomized complete block design (RCBD) was adopted with a factorial experiment with three factors and three replication. The experiment was carried out in one of the fields of Al-Taliáh sub-district/Babylon governorate to find out the allelopathic effect of root exudates of mungbean (Vigna radiata L.) and maize (Zea mays L.) affected by metabolic factors, fertilizer and mechanical stress on some germination indicators of cowpea seeds (Vigna unguiculata L.). The allelopathic effects of root exudates varied on the studied traits, as root exudates of mungbean caused a significant decrease in radicle length (RL), seedlings length (SL), and vigor index (VI) of cowpea plants for treatments affected by chemical fertilizer and not affected by mechanical stress, and a significant decrease in radicle length for treatments affected by mechanical stress and organic fertilizer, and a significant decrease in seedlings length and vigor index for treatments affected by mechanical stress and biofertilizer.