The pH-controlled encapsulation into and release of macromolecules from the monodispersed poly(vinyl amine) (PVAm) hollow particles was described. Poly(vinyl amine) hollow particles were simply produced by hydrolysis of poly(N-vinlyformamide) particles. And then, various molecular weights of macromolecules were encapsulated by using the swelling behaviors of the PVAm hollow particles.