[Objective] Various methodologies have been employed for memory rehabilitation, such as environmental control, improvement of learning methods, compensatory strategy training, or group-based interventions based on the characteristics of the patients. In some cases, however, these approaches have been reported to be inappropriate for patients suffering from marked memory deficit. Therefore, new, more effective approaches for recovery of memory deficit are needed. Several previous studies have reported that physical activity and exercise can affect cognitive function. However, empirical evidence obtained from patients with memory deficit is still insufficient. The aim of this study was to clarify the effect of aerobic training on memory ability in a patient with memory deficit. [Methods] The subject was a 48-year-old, right-handed male with memory deficit subsequent to hypoxic encephalopathy. We used an A-B-A single-case experimental design. The word delayed recall task and word fluency task were conducted 10 times in each phase. During the baseline A and washout A-phases, after memorizing 3 words, the subject performed a paper and pencil task for 15 minutes, and thereafter recalled the 3 memorized words and performed the word fluency task. During the B-phase, after memorizing 3 words, the subject pedaled a bicycle ergometer at 50W for 15 minutes, and thereafter performed the recall and word fluency tasks. [Results] Average performance in the delayed recall task was 0±0 words in the baseline A-phase, 2.3±1.1 words in the B-phase, and 0.1±0.3 words in the washout A-phase (F(2,18)=37.098, p<0.0001). That in the word fluency task was 2.7±0.9 words in the baseline A-phase, 2.3±1.3 words in the B-phase, and 3.6±1.3 words in the washout A-phase. [Discussion] These results suggest that aerobic training can lead to recovery of memory deficit. However, although we were able to observe acute effects, comprehensive recovery of cognitive function was not achieved, and the long-term effect was not tested. Further research is needed in this area.