The present invention aims to provide spherical biodegradable particles which have improved flexibility, cause less aggregation among particles, and have improved particle shape-recovering ability after passing through a catheter or the like, and a method for producing the particles. The present invention provides biodegradable particles comprising a synthetic polymer chemically cross-linked to a polyvalent carboxylic acid, which biodegradable particles have a water content of 20 to 90% in the water-saturated state.
