The effect of processing conditions (heating temperature, reaction time, and pH) and ingredients of beef flavor system (including enzymatic tallow hydrolysate, DL-methionine, L-cysteine, glucose, and D-xylose) on 3-monochloro-1, 2-propanediol (3-MCPD) esters concentration, and sensory characteristics of beef flavors are investigated. The results indicates that DL-methionine and L-cysteine had similar effects on the content of 3-MCPD esters, promoting their formation at low concentration, whereas, reducing them when added at high concentration. 3-MCPD esters concentration increases with increasing enzymatic tallow hydrolysate and D-xylose concentration. However, the addition of glucose has no significant effect on 3-MCPD esters concentration. Considering 3-MCPD esters concentration and sensory characteristics, the optimal addition of flavor precursors is finally selected as: Enzymatically hydrolyzed tallow (10%), L-cysteine (1.2%), DL-methionine (1.2%), glucose (1%), and D-xylose (0.5%). In addition, 3-MCPD esters concentration is also strongly dependent on heating temperature, reaction time, and pH. In conclusion, beef flavor is prepared using the optimal concentrations of flavor precursors and heated at 110 C with initial pH 7.0 for 100 min.Practical Application: This study provides a promising way of controlling the formation of 3-MCPD esters without changing the flavor quality of savory flavors. It promotes the food safety control technology of savory flavoring from passive defense to active forewarning. Also, it provides theoretical guidance and technical support for the sustainable and healthy development of savory flavoring industry.