Abstract: Many researches have been conducted to improve fallow system, and the results disseminated to farmers.Notwithstanding these, farmers still use their Indigenous Technical Knowledge (ITK) in fallow practices to achieveapproximately the same result with scientific method. This is why this research examines the factors that are related to theuse of indigenous knowledge on fallow practices by small-scale food crop farmers in Iseyin Local Government Area ofOyo State. The findings show that majority of the farmers were above 40 years with no formal education and still practiceindigenous fallow system despite their contact with extension agents. It was also found that the use of IndigenousKnowledge on fallow practices have strong relationship with fanner’s age, educational level, social participation, contactwith extension and sources of information. These variables however could explain 58 per cent of the variation inindigenous knowledge use on fallow practices adopted respectively by farmers. Significant determinants were age (t =1.61), gender (t = 2.65), household size (t = 2.06), marital status (t = 1.65), social participation (t = 2.82), farm size (t =1.89), farming experience (t = 2.65) and income (t = 1.73).