A polystyrene-supported, pyrrolidine-based catalyst depicting very high activity and excellent stereoselectivity in the anti-Mannich reaction of aldehydes and ketones has been developed. The very robust, immobilized catalyst has been successfully used in the implementation of a continuous flow process with short residence times (down to 6 min) for the production of highly enantioenriched anti-type Mannich adducts at the preparative scale.