Organic semiconductor materials have been widely used in photodetectors due to their eco-friendly property and excellent photoelectric property. In this paper, a novel Se/Spiro-MeOTAD heterojunction is fabricated by the spin-coating method combining p-type organic semiconductor materials Spiro-MeOTAD and Se microtube (Se-MT). The Se/Spiro-MeOTAD photodetector has excellent responsivity and switching ratio in the wavelength range from 350 nm to 800 nm and consumes no extra bias voltage, which shows favorable self-powered photoelectric properties. Compared with a single Se-MT device (0.1 V), the Se/Spiro-MeOTAD photodetector improves the responsivity by 10 times to 36.5 mA·W^-1 when the wavelength is 410 nm and the bias voltage is 0 V. The switching ratio is 156 (an enhancement of 800%), and the rise time and decay time reduce to 22 ms and 35 ms, respectively. The results show that organic semiconductor materials can effectively improve the photoelectric properties of inorganic semiconductors, and inorganic/organic heterojunction can be used to fabricate high-performance photoelectric devices.