This paper is a report of a study conducted to evaluate the unit cost of Thai massage at Thai Traditional Medicine Centre in Huayploo Hospital, Thailand. A retrospective cost analysis was performed on body massage services in 2013 fiscal year. The data on the costs of the direct costs were retrieved from the center records of Thai Traditional Medicine Centre, Huayploo Hospital. The indirect cost which had no record were estimated by the Head of Thai Traditional Medicine Centre. The unit costs of massage were calculated based on the activity-based costing. The unit cost analysis begins with the construction of a detailed flow diagram incorporating each activity in the process of massage. The cost of each activity is then calculated, and the two are linked. One-way sensitivity analyses were undertaken where each parameter was varied through a range of plausible values (rate of service utilization per day and direct massagers’ wage) and changes to the base results were observed. Total cost of massage service in 2103 was 4,546,155.02 Thai baht. The major driver of costs was personnel cost, which accounted for 79.49% of the total. Unit cost of massage service was 254.19 Thai baht per visit. As can be seen, direct cost, which comprises personnel costs for massage service is the largest proportion that impact directly to unit cost. Further sensitivity analysis using personnel cost and volume of visit factors revealed that the unit cost varied from 262.27 to 270.35 baht and from 241.76 to 193.06 baht, respectively. The results are a starting point for further investigations aimed at the exploitation of resources absorbed by Thai Traditional Medicine Centre opposed to the need to provide clients with the best possible services. In conclusion, massage cost analysis provides detailed information about the costs which may be used to manage the suitable costs with quality of service.