Organic semiconductor materials have shown unique advantages in the development of optoelectronic devices due to their ease of preparation, low cost, lightweight, and flexibility. In this work, we explored the application of the organic semiconductor Y6-1O single crystal in photodetection devices. Firstly, Y6-1O single crystal material was prepared on a silicon substrate using solution droplet casting method. The optical properties of Y6-1O material were characterized by polarized optical microscopy, fluorescence spectroscopy, etc., confirming its highly single crystalline performance and emission properties in the near-infrared region. Phototransistors based on Y6-1O materials with different thicknesses were then fabricated and tested. It was found that the devices exhibited good visible to near-infrared photoresponse, with the maximum photoresponse in the near-infrared region at 785 nm. The photocurrent on/off ratio reaches 10², and photoresponsivity reaches 16 mA/W. It was also found that the spectral response of the device could be regulated by gate voltage as well as the material thickness, providing important conditions for optimizing the performance of near-infrared photodetectors. This study not only demonstrates the excellent performance of organic phototransistors based on Y6-1O single crystal material in near-infrared detection but also provides new ideas and directions for the future development of infrared detectors.