Living mulches are cover crops grown simultaneously with and near main crops. Advantages of living mulches over dead cover crops may include increased weed suppression, reduced erosion and leaching, better soil health, and greater resource-use efficiency. An experiment was conducted at Horticultural Research Station, Kahikuchi Guwahati, Assam Agricultural University, Assam during Rabi 2019-20 and 2020-21 to investigate the effect of living mulches on weed control and its subsequent effects on yield of french beans. The treatments were french beans interplanted with living mulches of field pea (Pisum sativa) (FP), Berseem (Trifolium alexandrinum L) (B), Faba beans (Vicia faba) (FB), Conventional weed management (CWM) and weedy check (WC). The pooled mean highest weed infestation was recorded in WC which accounted for the highest weed dry weight (WDW) (75.23 g/m2). The weed control efficiency was recorded as average pooled mean of 61.35, 60.26 % in CWM and LM with berseem respectively for both the years. The conventional method and living mulch of berseem have improved french beans yield by 1.11, 0.94 t/ha of pooled mean of two years. Among the living mulches used french beans and berseem interplant suppressed weeds. The highest net returns ( 26056/ha) and B:C (3.45) were in CWM fb LM with B with net returns ( 24625/ha) and B:C (3.10) in both the years respectively. Hence, apart from the conventional method of weed management, berseem is an ideal weed suppressant and can be interplanted as a living mulch crop in french beans cultivation.