Fabrication and characteristic research of electrically controlled holographic polymer dispersed liquid crystal (H-PDLC) gratings which are simultaneously sensitive to red, green and blue laser beams are reported. Two different systems with photoinitiator and coinitiator, rose Bengal and N-phenylglycine, methylene blue and ptoluenesulfonic acid, as well as silver nanoparticles are employed in pre-polymer and liquid crystal mixture to record volume gratings formed under three laser beams (632.8, 532, 441.6 nm). The diffraction efficiency and electro-optical characteristics of the gratings are experimentally measured and studied. In addition, diffraction of the three primary colors is used to display image to demonstrate the image splitter function of left and right eyes for autostereoscopic display. The experimental results show that the tri-color excited gratings have high diffraction efficiency and good electro-optical characteristics under red, green and blue laser beams, and they have potential application prospect in autostereoscopic display and some other related fields.