The invention relates to the technical field of electric light source illumination and specifically discloses a double-half-bridge injection phase-locking power synthesis halogen lamp group. The halogen lamp group comprises a power supply filter, bridge rectifiers, a power factor correction device APFC, a halogen lamp group, a reference crystal oscillator, a frequency divider, two self-sustained oscillation chips 4, 6, a half-bridge inverter A, a half-bridge inverter B, and an addition coupler. RC oscillators of the two self-sustained oscillation chips 4, 6 are connected with a resistor R11 and a capacitor C15 for synchronous oscillation. The self-sustained oscillation chip 4 and a half-bridge inverter A output power transformer T2, and the self-sustained oscillation chip 6 and a half-bridge inverter B output power transformer T3 are fed into the addition coupler in a reverse-phase manner. The synthesized power is accessed to the halogen lamp group for turning the halogen lamp group on. Signals of the reference crystal oscillator are injected into the RC oscillators of the two self-sustained oscillation chips 4, 6 through the frequency divider for phase locking, and thus large-power illumination is achieved, and luminance declination caused by power unbalance resulted from oscillation frequency change since temperature rise of a device is too high is avoided. The halogen lamp group is suitable for commercial decorative large-power spotlight illumination occasions.