Abstract: The spirulina is a phototrophic organism. It was considered as the best of nutritional health product. The nitrogen atoms of spirulina was replaced with ¹⁵N stable isotope by the method of biosynthesis. So ¹⁵N labeled spirulina is a nutritional health product and stable isotope tracer product. As a tracer, ¹⁵N labeled spirulina plays an irreplaceable part in bioscience, medicine metabolism and pathology metabolism and so on. ¹⁵N label spirulina is cultivated only in a small scale because of expensive ¹⁵N material. The culture temperature, shine intensity, pH for spirulina were studied. Some feasible conditions were obtained such as 25 ℃, 3 000-4 000 lux, initial pH9.0 in the room. ¹⁵N label spirulin prescription was obtained via orthogonal experiment. The optimize prescription of spirulina was that sodium bicarbonate was 13 g·L^-1, ¹⁵N-urea was 0.2 g·L^-1, potassium phosphate dibasic was 0.6 g·L^-1, and glucose was 2 g·L^-1. The cost of ¹⁵N material has a significant reduction. The abundance was more than 98%.