Royal jelly is composed of different components such as proteins, amino acid, fatty acid, and sugars. Protein is a major factor which cause allergy. We focused on water soluble royal jelly (WSRJ) that was removed allergy - inducing protein. WSRJ isolated from 70% ethanol extraction and neutralization. We confirmed that WSRJ was removed allergy - inducing protein, 48kDa and 55kDa band via SDSPAGE. 10-hyroxy-2-decenoic acid (10-HDA) content analyzed by using high performance liquid chromatography. 10-HDA content of WSRJ is 2.42g/100g, which is double compared to that of lypophilized RJ. Also, 1-0.01ug/ml concentration of WSRJ increased significantly human dermal fibroblast (HDF) proliferation for 48hr. The results indicated that WSRJ removed allergy-inducing protein increased 10-HDA content, which lead to HDF proliferation.