Inverse opal photonic crystals of Eu3+ doped LaPO4 (LaPO4: Eu）were prepared by a self-assembly technique in combination with a sol-gel method. In the preparation process, Eu3+ doped LaPO4 precursors were filled into the interstices of the opal template assembled by monodispersive polystyrene microspheres. The polystyrene template was then removed by calcination at 650 °C for 5h, meanwhile, Eu3+doped LaPO4 inverse opal photonic crystal was formed. The photoluminescence (PL) from Eu3+ doped LaPO4 inverse opal photonic crystal was studied. The effect of the photonic stop-band on the spontaneous emission of Eu3+ has been observed in the inverse opal photonic crystals of Eu3+ doped LaPO4. Significant suppression of the emission was detected if the photonic band-gap overlaps with the Eu3+ ions emission band.