The application of health logistics to patient referral management, from the sub district health promoting hospital (SHPH), which is the primary healthcare provider, to the district hospital, which is the secondary healthcare provider, is very crucial for increasing the health service efficiency to save patients’ lives in due time. This research aimed to study the patient referrals from the SHPHs to the district hospitals in Chachoengsao Province, Thailand based on the current operating conditions and to design a patient referral system with the shortest time period by conducting analysis with a geographic information system (GIS). The proposed method employed the analysis of positioning problems using the location-allocation analysis, so that the district hospitals cover the services of the SHPHs. Results indicate that the patient referrals from the SHPHs to the district hospitals under the current operating conditions took 1,999.12 minutes because it is required by the regulations that the patient referrals be within the same district. However, when analyzing the total time under the shortest time condition, the referrals took 1,893.34 minutes. Additionally, the comparison results of the patient referrals under the current operating condition showed that the referral time of 24 SHPHs decreased by 105.78 minutes or 20.61%. These research results can be useful for planning the patient referrals from the SHPHs to the district hospitals of Chachoengsao Province and to develop an efficient referral service for timely medical assistance.