The aim of present study was to evaluate efficacy of Modified Co-Synch Plus Protocol with or without progesterone device for estrus induction, progesterone concentration and conception rate in Murrah buffaloes under field conditions during summer season. The study was conducted using 30 postpartum anestrus Murrah buffaloes divided in two groups. In Group 1 (n=15), the buffaloes were administered with PMSG 400 IU on -3 day, Buserelin acetate 10 micro g, on day 0, cloprostenol 500 micro g, on day 7, and on day 9 h CG 2000 IU. Thereafter, timed artificial insemination (TAI) was done at the time of h CG injection and 24 h later once again. In Group 2 (n=15), the buffaloes were treated with same protocol as Group 1, in addition to progesterone device, which was placed in vagina on day 0 and was removed on day 7 of the protocol. Thereafter, TAI was done as in Group 1. Plasma Progesterone concentration was estimated during the different days (-3, 0, 7, 9 and 10 day) of protocol. The estrus induction rate was 86.6 percent and 100 percent in Group 1 and Group 2 respectively showing very good estrus (46 percent), good estrus (30.7 percent) and poor estrus (23.07 percent) in Group 1 while very good estrus (46.6 percent), good estrus (40 percent) and poor estrus (13.4 percent) in Group 2. The conception rates in Group 1 and 2, at FTAI and overall including subsequent estrus were 46.2 percent and 61.53 percent and 53.33 percent and 73.33 percent respectively. The plasma progesterone concentrations were higher (P LT 0.05) on day 7 in Group 2 than Group 1 (4.16+-0.32 vs 2.30+-0.24 ng/ml). Both two protocol treatment during non breeding season resulted in very good estrus induction and acceptable conception rate in anestrous buffaloes.