Abstract: Heme was extracted from horse blood, using ultrasound method combined with CMC-Na. Based on the single factor experiment, the Box- Behnken design and response surface method were used to set up the mathematical model and determine the best extraction conditions.As a result, the optimum process conditions were obtained as following: ultrasonic power was 338W, ultrasonic time was 10min, deionized water content was 5 times the size of red blood cells ( RBC) , and extraction pH was 5.5.Under these conditions, the yield of heme reached maximum 0.42g /50mL which was in good agreement with the predicted value.