Purpose : The purpose of this study was to evaluate the reliability analysis of the deep tendon reflex by using electromyography (EMG). Methods : The study was tested on 30 volunteers who are women in their 20s. Using an electronic reflective hammer of EMG, deep tendon reflex was measured on all subjects with the participation of three trained physical therapists as raters. First, the subjects were comfortably seated on a table with their knees bent at 90 °. The three raters tapped the electric hammer at intervals of 10 seconds to avoid habituation until a total of 10 compound muscle action potential records were collected. Intraclass correlation coefficients (ICCs) were calculated to assess the inter-rater reliability of the deep tendon reflex with the use of EMG. The items of analysis included amplitude (㎷), latency (㎳), duration (㎳), and area (㎷ × ㎳) of the compound evoked potentials. Results : Based on the average records of 10 compound muscle action potential, excellent reliability (ICC: .912) was achieved in terms of area, and there was good reliability in terms of latency (ICC: .795) and duration (ICC: .800). In the shortest latency of the compound muscle action potential, good reliability was achieved in terms of amplitude (ICC: .865), duration (ICC: .781), and area (ICC: .832). In the amplitude of peak-to-peak of compound muscle action potential, excellent reliability was recorded in terms of amplitude (ICC: .924), and good reliability was recorded in terms of duration (ICC: .801) and area (ICC: .874). Conclusion : The findings in this study indicate that electromyography via an electric hammer is a reliable method of assessing and measuring deep tendon reflexes. Especially, it may be an excellent gauge in the area of average values of the compound muscle action potentials and the amplitude of peak-to-peak of compound muscle action potentials.