Abstract: A castor oil-modified and ketone containing polyurethane dispersions (PUDs) were obtained using 2,2-bis(4-(2-hydroxypropoxy levulinate)phenyl)-propane (BHLPP), 4,4-methylenedicyclohexyl diisocyanate (HMDI), dimethylolpropionic acid (DMPA), polyneopentylene adipate glycol (PNA), castor oil (CO) and adipic dihydrazide (ADH) as raw materials. PUD films were characterized by ATR-FTIR. Effects of molar ratio of NCO/OH, DMPA, CO and BHLPP contents on dispersion and film properties were investigated. The results show that water resistance, solvent resistance and mechanical properties are enhanced with the increase of CO and BHLPP contents. When n_NCO/n_OH, DMPA content, CO content and BHLPP content are 1.8, 24 mmol·(100 g resin)^-1, 13.5 g·(100 g resin)^-1 and 12.9 g·(100 g resin)^-1, respectively, the castor oil-modified and ketone containing PUD has good resistance to water, solvent and heat. The pencil hardness of the film reaches to 2 H.