The purpose of this study was to verify the forms of the effect of serial position effects of memory according to the illuminance of light. This study was conducted as an experimental method, and 21 adults without cognitive impairment participated in the study. The illuminance condition was designed with high illuminance condition of 1,000 lx and low illuminance condition of 300 lx. The memory task used word list of 20 items consisting of a series of pointless spellings. After memorizing the word list for 10 minutes, the participant performed a retention task 24 hours later. The memory retention task consisted of filling the empty part of the learned word and completing the word. The analysis was performed by dividing the word items into three conditions: primacy, middle, and recency. Primacy used the first item in the word list, Middle used the 10th item in the middle of the word list, and finally Recency used the last item in the word list for analysis. The result was F = 4.16 (p = .02), and showed that there was a statistically significant difference in memory retention of primacy, middle, and recency at 95% confidence level in dim condition.