Objective : I will study about similarities and differences of furunculus section between Sonjininchungeumbang and Bigeupchungeumyobang. Method : I compare furunculus section of Sonjininchungeumbang with Bigeupchungeumyobang to investigate changes of texts. Result : I can find significant differences of furunculus section between Sonjininchungeumbang and Bigeupchungeumyobang, specially the 3rd prescription of Balbae(發背方第三), the 6th prescription of Pyojeo(?疽方第六). Conclusion : Sonjininchungeumbang is a prescription book which is compiled in Dang dynasty. And Bigeupchungeumyobangis is a revised version of Sonjininchungeumbang which is compiled by the Bureau for Revising Medical Texts(校正醫書局) in Song dynsasty. Bigeupchungeumyobangis shows the added medical knowledge about furunculus in Song dynsasty.