The present invention relates to a method of producing blowfish yukgaejang (Korean traditional spicy soup). More specifically, the method of producing the blowfish yukgaejang includes a first step, a second step, a third step, a natural blowfish seasoning preparing step, a blowfish broth producing step, and a mixing step. The first step is a step of preparing the blowfish, trimming the bowlfish by a qualified person to remove a bone, an internal organ, teeth, and blood, washing the bowlfish, heating and steaming the bowlfish at the temperature of 95-105°；C for 5-8 minutes, and tearing blowfish flesh. The second step is a step of preparing a supplementary material including bracken, taro, and large scallion. The third step is a step of preparing sauce by mixing 55-65 wt% of red pepper powders, 5-20 wt% of oil, 10-15 wt% of soy sauce, 5-10 wt% of crushed garlic, 1-4 wt% of crushed ginger, 5-10 wt% of salt, and 1-5 wt% of black pepper together. The natural blowfish seasoning preparing step is a step of preparing natural blowfish seasoning by mixing and grinding 20-35 wt% of dried blowfish, 10-25 wt% of dried shiitake mushroom, 10-25 wt% of dried anchovy. The blowfish broth producing step is a step of putting 10-30 wt% of blowfish bones, 50-100 wt% of beef leg bone broth, 5-40 g of radish, onion, scallion, and kelp, 1-3 g of whole pepper, 1-5 g of red pepper seeds into 15 L of water, heating the mixture at the temperature of 100-120°；C, boiling the mixture for 30 minutes to 1 hour, and withdrawing the radish, onion, scallion, kelp, whole pepper, and red pepper seeds, and heating the result at the temperature of 100-120°；C, and simmering the result on low heat for 2-9 hours if the result is boiled once to produce the broth. The mixing step is a step of putting the broth, which is produced in the on low heat for 2-9 hours, in a container, placing the prepared supplementary material on the broth, putting the natural blowfish seasoning, and the sauce into the conta
