The present invention relates to a method for preparing seaweed pickles, which uses costaria costata, instead of general seaweeds to prepare pickles with a soft and chewy texture. According to the method of the present invention, costaria costata has a scent of rosemary and apple mint, and thus not only removes an unpleasant odor but also stimulates appetite. Further, fermented soy sauce is used instead of ordinary soy sauces to prepare seaweed pickles and thus the pickles have excellent flavors. The method for preparing seaweed pickles, according to an exemplary embodiment of the present invention, comprises: a first step of removing salt by defrosting 15 to 25 parts by weight of costaria costata with flowing water for 11 to 13 hours a second step of soaking the defrosted costaria costata in a container with water for two and a half hours to three and a half hours, wherein 0.045 to 0.055 parts by weight of rosemary and 0.045 to 0.055 parts by weight of apple mint are inputted in the water a third step of preparing fermented soy sauce by mixing 2.8 to 3.2 parts by weight of soy sauce, 2.8 to 3.2 parts by weight of vinegar, and 2.8 to 3.2 parts by weight of sugar, adding 0.045 to 0.055 parts by weight of a bay leaf to the mixture, and boiling the mixture added with the bay leaf for two to three hours to prepare fermented soy sauce a fourth step of placing the costaria costata with a scent of rosemary and apple mint, prepared in the second step, in a fermenter and inputting the fermented soy sauce prepared in the third step into the fermenter to mature the costaria costata at the temperature of 4-10°C for two and a half hours to three and a half hours and a fifth step of packing the costaria costata completely matured in the fourth step for shipment.COPYRIGHT KIPO 2016본 발명은 일반 미역이 아닌 쇠미역을 이용하므로 씹는 맛이 훨씬 좋은 장아찌를 만들 수 있으며, 쇠미역에서 로즈마리와 애플민트의 향이 베어 나도록 함으로써 쇠미역의 잡내를 잡을 수 있음은 물론 쇠미역의 잡내를 잡을 수 있음은 물론 입맛을 돋우는 효과가 있으며, 일반적인 간장이 아닌 발효청을 사용함으로써 풍미가 뛰어난 해초 장아찌의 제조방법에 관한 것이다.본