The research assessed the effect of famer- field school extension approach on rural crop farmers in conflict-affected communities in Adamawa State, Nigeria. The study used multi-stage, purposive and random sampling to select five Local Government Areas (LGAs), three communities and 150 beneficiaries for the study. A similar procedure was also used to select 150 non-beneficiaries to serve as a control group. Descriptive statistics, average treatment effect (ATE) and statistical test (t-test) were employed for the data analysis. Findings revealed that all the technologies introduced recorded over 50% adoption except for seed germination test, disease control and ploughing. A total of 91.3% adopted land selection and 80.7% adopted seed selection, while only 30.0% adopted seed germination test. The findings also revealed that increases in farm size, output, and income were significant at P <0.05 among the beneficiaries compared to non-beneficiaries. Also, the beneficiaries had significant improvement in consumption expenditure and social cohesion at P <0.05 compared to the non-beneficiaries. In conclusion, participation in FFS has achieved a significantly positive effect on the livelihood of rural crop farmers in the study area. It is recommended that considering the huge impact of the approach on the beneficiaries within a short period of time, the programme should be extended to other LGAs in the state for wider coverage of the benefits.