Narrowband photodetectors have attracted considerable attention owing to their ability to suppress interference from nontarget wavelengths. However, operation of sensitive narrowband detection usually requires a high driving voltage, which leads to high power consumption and severe degradation of device performance. In this study, a narrowband 1050 nm photodetector with high sensitivity and excellent wavelength selectivity was realized using a simple ${p}$ -type Si Schottky junction. The device exhibited a high responsivity of 810 mA/W and a large linear dynamic range of 128 dB at zero bias. At a low bias voltage of −3 V, its external quantum efficiency increased to ${6}.{9}\times {10} ^{{3}}$ %, with a full width at half maximum of approximately 74 nm. This outstanding device performance can be ascribed to the unique geometry of dual Ti /Ag Schottky electrode and the gain mechanism derived from the large transit-time difference between the photogenerated electrons and holes. This study opens new avenues for the development of highly sensitive narrowband photodetectors with low driving voltages in the future.