Sabaiksan has been prescribed to treat various allergic diseases in herbal medicine which were induced by various vasoactive amine released from the mast cells. The constituents of Sabaiksan are Mori Cortex Radices(MCR), Lycii Cortex Radicis(LCR) and Glycyrrhizae Radix(GR). Recently, simple models of compound 48/80 induced anaphylactic shock and cutaneous reaction in vivo were developed to test various agents employed in the field of allergy and toxicology research. The purpose of this study is to evaluate the effects of Sabaiksan on compound 48/80 induced anaphylactic stock, cutaneous reaction and mesenteric mast cell degranulation rate in ICR mice, and on compound 48/80 induced peritoneal mast cell degranulation and histamine release in vitro. Groups of ICR mice were intraperitoneally pretreated with $100{mu}{ell}$ of saline, $MCR(2g/m{ell}),;LCR(2g/m{ell}),;GR(g/m{ell})$ or Sabaiksan itself(MCR+LCR+GR) at 24, 12 and 1 hour before compound 48/80 solution ($10{mu}{ell}/gm$ B. W) were peritoneally given into them, and then mortality within 72 hours after the compound 48/80 injection, and mesenteric mast cell degranulation rate at 15 minutes after compound 48/80 injection were calculated. In vitro experiment, $400{mu}{ell}$ of rat peritoneal mast cell suspension$(10^6cell/m{ell})$ were pretreated with $50{mu}{ell}$ of saline, $MCR(2g/m{ell}),;LCR(2g/m{ell}),;GR(g/m{ell})$ or Sabaiksan itself at room temperature for 30 minutes, and then $50{mu}{ell}$ of compound 48/80 solution $(100{mu}g/m{ell})$ were added into it. 30 minutes after the addition of compound 48/80 solution, histamine release assay in the supernatant of peritoneal mast cell suspension were performed employing radioisotope enzymatic assay and morphologic changes of mast cells in each regular time point were photographed. Compared with controls, compound 48/80 induced anaphylactic shock was significantly inhibited by MCR and GR pretreatment into the ICR mice. Significant inhibition of compound 48/80 induced cutaneous reaction, mesenteric mast cell degranulation rate in vivo and histamine release from the rat peritoneal mast cells in vitro was observed only in MCR pretreated group. From the above results, it is suggested that MCR component of Sabaiksan may playa key role to suppress mast cell function since it has been applied to various allergic diseases.