The invention discloses a capacitance impedance balanced type multichannel LED drive circuit, comprising a direct current input power supply, a half-bridge switch circuit, a resonant inductor, a resonant capacitor, a parallel inductor, a transformer, a variable capacitor circuit, a balanced capacitor module, an LED string light module, a feedback control module and a constant frequency control module. N LED string light loads in the LED string light module are connected with n balanced capacitors in the balanced capacitor module in series and then are connected with a secondary side of the transformer in parallel. The constant frequency control module is responsible for controlling switch-on and switch-off of switch tubes in the half-bridge switch circuit. The feedback control module samples a secondary output voltage and a primary resonant current of the transformer, compares the secondary output voltage with a required reference voltage and then generates signals for controlling the switch tubes in the variable capacitor circuit. According to the circuit, a half-bridge switch frequency is fixed, output is controlled by adjusting an equivalent resonant capacitance, a load impedance characteristic is not influenced by the switch frequency, automatic current sharing is realized, and an LED light string open circuit protection function is achieved.