Ipomoea carnea subsp. fistulosa (bush morning glory) is a alien invasive weed species, native of Latin America, spread throughout the fresh water ecosystems of tropic and sub – tropics . I. carnea subsp. fistulosa infestation generally found in undisturbed areas, through release of allelochemical monopolise the natural resource, thus replace the original native species , . Water from fresh water tanks and pond obviously feed to rice crop. Allelopathic effect of I. carnea subsp. fistulosa is not reported on any crop plants. This is the novel work which examine the allelopathic effect of I. carnea subsp. fistulosa aqueous leaf extract on rice. The leaf samples for aqueous extract collected from near by infestation. Here, aqueous leaf extract treatments namely 5, 10, 15, 20 per cent and control (distilled water) employed. Two sets of germination experiments were conducted viz., petri dish method and roll towel method with 25 seeds each. Periodic observations clearly indicates the potential inhibition of leaf aqueous extract of I. carnea subsp. fistulosa on rice crop germination.