A circuit board of a parallel light-emitting circuit of parallel LED light-emitting device has an electrical insulation board, two wire patterns and at least two power wires. The two wire patterns are oppositely formed on the electrical insulation board. Each wire pattern is connected to the corresponding power wire and has a matrix main loop having closed loops and a plurality of sub-wires formed inside the corresponding closed loop. A plurality of LEDs are respectively mounted on the corresponding closed loop and electrically connect with the two sub-wires of the two wire patterns. When a DC power supply is inputted to the power wires, a current of the DC power supply uniformly flows through the matrix main loop and the sub-wires, so that the LEDs electrically connected to the corresponding sub-wires receive approximately equal current to further emit light with uniform brightness.