The invention discloses a piano training aiding device, mainly relating to the field of piano training auxiliary instruments. The piano training aiding device comprises a bottom board, wherein two bases are arranged on the bottom board, through holes are vertically formed in the bases, support posts are arranged in the through holes, a support plate is arranged on the tops of the support posts, two arc-shaped brackets are arranged on the top of the support plate, an upper clamp plate is arranged at one side of the bottom board, two support frames are arranged on the bottom of the bottom board, locking screws are arranged on the support frames, support blocks are arranged on the locking screws, lower clamp plates are arranged at one sides of the support blocks, a mounting plate is vertically arranged on the bottom of the support plate, a plurality of laser lamps are arranged on the mounting plate, and a control box is arranged on the bottom of the support plate. The piano training aiding device can be firmly fixed at the front end of a piano, so that support can be provided for the elbows and forearms of a player, meanwhile, the support height can be adjusted according to the demands, thus the playing posture of the player can be standardized, and the training on the piano playing reaction speed can be realized.