Abstract: In order to make use of pig blood sufficiently and provide colorant which possesses excellent color and is rich in nutrition for meat products, hemoglobin solution was seperated from fresh pig blood and semidry solid nitrosohemoglobin was prepared with vitamin C as reducer and sodium nitrite as color fixatives and the preparation of hemachrome is not necessary. Single factor experiment was conducted to determine the best range of additon of sodium nitrite, addtion of vitamin C and heating time in which chromogenic rate of the prepared nitrosohemoglobin is higher. orthogonal test of three factors and three levels was conduted to optimize the technology. The results show that the optimum technology is as follows: hemachrome, sodium nitrite and vitamin C should be mixed in hemoglobin solution as the mol ratio of 1∶3∶12, heating temperature is 85℃, and holding time is 15min. The chromogenic rate of the nitrosohemoglobin prepared under this condition is 90.42%.