This study uses a framework of a food safety management system-diagnostic instrument (FSMS-DI), for the assessment of the context of a Chinese edible oil manufacture through the view of a case study, and an evaluation of the performance of the FSMS of a Chinese edible oil company. The study includes a structured interview with the quality assurance manager. FSMS-DI is used to diagnose the core control and assurance activities, as well as the riskiness of context factors and output of the system. A factory tour is done to verify the information collected during the interview. The company is operating in a low to moderate risk context. The control activities are overall operating at an advanced level, while the assurance activities are at an average level. Although the food safety output of the FSMS is good, improvements are advised on the assurance activities to develop towards a more robust FSMS. This study gives an insight into the current situation of implemented FSMS in view of the context riskiness of the food business. Quantitative studies and further exploration of typical Chinese context characteristics may help food safety authorities, supporting (branch of industry) organisations, and food companies to advance towards a more effective food safety control in the food sector.