Abstract: Chilling injury is when morphological and physiological damage is sustained by plant tissue that is exposed to freezing temperatures. An experiment was conducted using four chilling tolerant sweet potato genotypes such as 105MS1, 108MS2, 180MS3 and 183MS4, which were selected from seventy nine lines from three major variety crosses for tolerant to chilling injury. The effects of chilling exposure on fatty acids compositions and peroxidase enzyme activity were studied. Chilling exposure increased the Peroxidase Enzyme Activity (PEA). Genotypes differences were also found in PEA following chilling exposure. All four genotypes that were tested had a high level (over 50%) of unsaturated fatty acid on their glycolipids. There were no differences found for the fatty acid percentage composition of the total glycolipid and phospholipid fractions from the four chilling tolerant genotypes except for C18:0 of the glycolipid fraction. However, C18:0 was found in low percentage and was not considered a major fatty acid. Sixty percent of total fatty acid in glycolipid fraction was C18:2 and C18:3. It was concluded that if lipids fatty acid composition was indeed a factor in chilling tolerance, it did not vary among the chilling tolerant genotypes. The result suggests that the genotypes were considered chilling tolerant to chilling environment, but that differences existed in their mechanism for tolerance. Thus, by breeding and selecting for chilling tolerance, it could enhance chilling tolerance in sweet potatoes.