The present study was conducted to assess the constraints faced by Farmers Field School (FFS) farmers and trainers in implementation of FFS methodology. A total of three districts were selected purposively from three regions of Andhra Pradesh based on the largest area under paddy cultivation. Respondents were selected through simple random sampling procedure. The total sample size was 240 comprising 120 FFS farmers and 120 non-FFS farmers. Garrett’s ranking was used to rank the constraints at farmer and trainer level. Study revealed that shortage of integrated crop management (ICM) experts’ and ‘lack of extension back up’ with a mean score 50.03 and 47.35 were the two most important institutional constraints reported by the farmers. With regard to technological constraints ‘consumes more time’ (67.90) was the most important constraint followed by ‘shortage of skilled labour’ (49.82). In case of trainers with regard to institutional constraints, ‘overlapping of departmental schemes or programmes’ and lack of timely supply of inputs’ (59.38) were the top most institutional constraints. FFS trainers have opted ‘work over load’ as premier operational constraint with mean score of 56.18 followed by ‘lack of technical work group’ (46.75). ‘Fragmented lands’ and ‘Lack of vehicle or transport facility to reach remote area were the most important constraints faced by FFS trainers at village level. With respect to farmer level constraints the ‘fear of farmers about ICM technology’ with mean a score of 69.33 was ranked first followed by ‘the huge subsidy on fertilizers & pesticides’ (53.75). Above stated constraints under FFS methodology hindered the effective performance of FFS farmers and trainers.