Abstract : The aim of this research is to investigate the impact of Farmers Field School (FFS) on farmers knowledge, farmers groups capacity, process of adoption and dissemination of IPM in Bondowoso District. The population of this research was 442 group of farmers, with 25.244 who are engaged in the IPMFFS in Bondowoso District. This research conducted from August until November 2022. The sample for this research consisted of 400 farmers selected using a stratified regional random sampling method. Areas or regions are used as the basis for subdistricts. 8 sub-districts are randomly selected from 23 sub- districts and each sub-district is represented by two groups of farmers. The conclusion is that: IPMFFS has a significant impact on farmers' knowledge; IPMFFS improves three aspects of the capacity of farmers' groups, namely their capacity to plan activities to increase productivity, capacity to implement and obey agreement with other institution, and capacity to apply technology, information, and team work; IPMFFS has the capacity to improve the dissemination of Integrated Pest Management (IPM) by farmers and; the IPMFFS has the capacity to improve dissemination of IPM by the farmers.