Abstract.[Purpose] Memory impairment is a common sequela in patients with traumatic brain injury (TBI). Little is known about applications for memory training for patients with TBI. We investigated the effect of a memory training application in a patient with TBI. [Subjects and Methods] A 37 year-old male patient presented with memory impairment since onset of TBI resulting from a traffic accident. We developed a memory training application for use with a tablet PC. It consists of six stages. Each stage is composed of visual and auditory memory training parts. Two training sessions were conducted per day, five days per week, for a period of three months from nine months after onset to 11 months after onset.[Results] The patient's scores on the Memory Assessment Scale showed improvement after participating in the memory training program for a period of three months: global memory, 56.6%; short-term memory, 13.2%; visual memory, 75.0%; and verbal memory, 37.9%. [Conclusions] We observed significant improvement of memory function of this patient after memory training using this application. As a result of these findings, we believe that this application could be useful for improving memory impairment of patients with TBI.