The present invention is directed to providing a safe medical adhesive, a cured body of which is hard to be degraded and decomposed and thus stable and the cured body generates less amount of acid, aldehyde, etc. due to degradation/decomposition. The medical adhesive includes a hydrophilic urethane prepolymer (UP) obtained by reacting a polyisocyanate component (A) containing a fluorine-containing non-aromatic polyisocyanate compound (A1) as an essential ingredient and a polyol component (B) containing a hydrophilic polyol (B1) as an essential ingredient, wherein a chlorine content in a chlorine-containing organic compound based on the weight of the hydrophilic urethane prepolymer (UP) is 0.005 wt % or less.