The use of dichloro-diphenyl-trichloro-ethane and gamma-lindane has been limited in many countries but allowed to be used restrictively as prescription medicine in humans. However, in some developing countries, they are unscrupulously used in grains preservation. This study aimed at determining the concentration of DDT and γ-HCH in cowpeas collected from South-West states of Nigeria and determine the possible daily intake in these areas. Seventy-six samples of cowpeas were obtained from local markets in South-West Nigeria. Ten gramme of cowpea was weighed, pulverised, extracted with dichloromethane (150 ml) and cleaned-up using silica gel. The extracts were then analysed for DDT and γ-HCH using GC-MS with a Restek column. The mean concentration of γ-HCH was highest in Agege market (168.00±0.114) µg/kg in Lagos state, while Eleyele market (64.26±0.138) µg/kg in Oyo state had the highest mean concentration of DDT. Health index of 6.13 was obtained for γ-HCH in children. This study has shown that high level of DDT and γ-HCH were used in the preservation of cowpeas. The concentration of these pesticides exceeded the maximum residual limit (MRL), making the cowpeas probably unfit for human consumption.