The synthesis of high loading and recyclable pentaerythritol supported imidazolidin-4-one catalyst I and its application in enantioselective Diels-Alder reactions of cyclopentadiene and a,b-unsaturated aldehydes with high performance were described. Especially noteworthy, the pentaerythritol supported imidazolidin-4-one with high loading capacity can be recovered by simple precipitation and filtration, and recycled for up to four runs without observing significant decrease in catalytic activity. Graphical AbstractO + endo exo catalyst (10 mol% catalyst monomer) Solvent, T( o C) + CHO Ph Ph CH O HX (10 mol%)