alpha-Zirconium phosphate (alpha-ZrP) nanocrystals with different morphology and particle size were synthesized via three facile and mild methods, namely alpha-ZrP plates, alpha-ZrP nanoparticles-1 and alpha-ZrP nanoparticles-2. alpha-ZrP plates and alpha-ZrP nanoparticles were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and N2 sorption isotherms. The photocatalytic activity of alpha-ZrP plates and alpha-ZrP nanoparticles were explored by photodegradation of Rhodamine B under ultraviolet irradiation. 97% of Rhodamine B was degraded with alpha-ZrP nanoparticles-2 within 50 min, which is more efficient than alpha-ZrP plates and alpha-zirconium phosphate nanoparticles-1. All alpha-ZrP catalysts exhibited superior photocatalytic activity.