Consumption of starchy foods, such as yam, is a major risk factor for an increased glycemic index. However, the impact of different processing treatments, such as processing into chips, on the glycemic index of yam remains poorly studied. The objective of this study was to in vivo evaluate of the glycemic index of yam chips from the kokoro variety (species Dioscoreacayenensis-rotundata) grown in Benin. In vivo tests were carried out on Wistar rats fed successively with processed kokoro yam flour (obtained from yam chips using the simple method, soaking method, and with the addition of additives) and unprocessed (fresh yam). Blood glucose levels and the glycemic index were determined according to standard methods. The results showed that fresh yam and yam chip flour produced with the soaking method presented high (1.2 g/L) and lower (1 g/L) postprandial glucose levels, respectively. Fresh yam had the highest area under the curve (0.89 ± 0.25 g/L. min), while yam chip flour produced with the soaking method had the lowest area under the curve (0.64 ± 0.42 g/Lxmin). After calculating the glycemic index, yam chips had glycemic indices (40.25 ± 2.33% and 45.28 ± 3.38%) lower than that of fresh yam (55.97 ± 2.46%). These results demonstrate that transforming yam into chips significantly reduces the glycemic index, allowing yam chips to be classified among foods with a low glycemic index.