The balanced homodyne detection technique is the one of the main methods for the detection of squeezed state quantum noise in the low frequency range, in which the signal-noise ratio and saturation power are the important parameters limiting balanced homodyne detection. Based on the characteristic of inductance impedance changing with frequency, a current-voltage-conversion frequency function is adopted to make the conversion impedance corresponding to the low-frequency (or direct current) component of photocurrent is lower than that corresponding to the high-frequency part, and thus the saturation power and signal-noise ratio of the photodetector are both enhanced. By combining the instrument amplifier and trans-resistance operational amplifier circuit, a kHz balanced homodyne detector with high signal-noise ratio and high common-mode rejection ratio for direct current and alternating current output is obtained, whose measured common-mode rejection ratio is 54 dB. When the input power is 14.4 mW, the shot noise at 50‒100 kHz is 31 dB higher than the electronic noise and the saturation power of the detector is 17 mW.