The research was done with the aim of evaluating the effect of the basin tillage system as a method of conservation agriculture, on improving smallholder farmers’ food security in Mutasa, Manicaland Province in Zimbabwe. This research focussed on the 2010/2011 agricultural season. The main objectives of this study were to determine the contribution of CA basin tillage system on increasing yields per hectare, to evaluate which CA principles are being practiced by smallholder farmers, and to determine how many months the harvested maize will last. The study compares smallholder farmers who practiced CA with farmers who practiced other tillage methods. The other tillage methods are ploughing and conventional hand hoe tillage systems. On average the farmers who practiced CA used 0.47 hectares of land whilst farmers who practiced other tillage methods used an average of 0.43 hectares of land. The average amount of maize produced by smallholder farmers who practiced CA was 824 kg while who practiced other tillage methods produced an average of 498 kg. Farmers practicing CA produced yield with an average of 1175 kg/ha of maize grain while farmers who practiced other tillage methods produced an average of 946 kg/ha. Food security in this reaseach was measured by the amount of months the maize grain produced was lasting in relation with the household size. 57 percent of the farmers who practiced CA are food secure because they have maize grain to last them a full consumption year and moreover surplus. Only 27 percent of the farmers who practiced other tillage methods produced enough to last a full consumption year.