As the receiving terminal for quantum information systems, improving the photon detection efficiency and working frequency of single-photon detectors holds great significance. In this paper, we present a 2 GHz high-detection-efficiency single-photon detector utilizing an InGaAs/InP avalanche photodiode (APD). By combining sinusoidally gated operation with the low-pass filtering technique, the spike noise of the APD was effectively suppressed, achieving a noise rejection ratio of 41.5 dB. With high-frequency gated operation, the detection efficiency reached 40.2% at a wavelength of 1310 nm. The afterpulse probability was 10.0%, and the dark count rate was 7.75×10^-6 per gate when the APD was cooled to -10 ℃. The SPD also demonstrated excellent time resolution, with a time jitter of only 80 ps. To further improve the performance of the SPD, we adjust the amplitudes of the gate signal and operating temperatures. The presented SPD provides support for applications such as quantum communication and quantum computing.