Surface-microstructured silicon exhibits unique optical properties， demonstrating promising potential for applications in photoelectric sensors， solar cells， and related fields. To further explore the optoelectronic modulation effects based on its surface architecture， this study presents a novel heterojunction photodetector constructed by integrating MXenes （Ti₃C₂T_x） with microstructured silicon substrate through spin-coating and other fabrication techniques.Comparative studies were conducted on commercial silicon， microstructured silicon， and Ti₃C₂T_x/microstructured silicon devices under varying wavelengths and optical power densities. The current-voltage （I-V） characteristics and photoresponse performance reveal that the Ti₃C₂T_x/microstructured silicon photodetector exhibits significantly superior external quantum efficiency （EQE） and responsivity across a broad spectral range of 200-1750 nm compared to commercial silicon and microstructured silicon detectors. Notably， in the near-infrared region （1100-1800 nm）， the device demonstrates exceptional performance， achieving EQE exceeding 1000% and responsivity greater than 10 A/W. In contrast， commercial silicon photodetector in the same spectral range shows EQE below 10% and responsivity no higher than 0.3 A/W， while microstructured silicon photodetector exhibits EQE of below 15% and responsivity limited to 0.08 A/W. Further dynamic response and bias-dependent analyses indicate that the Ti₃C₂T_x coating， owing to its high conductivity and the built-in electric field formed at the heterojunction with microstructured silicon， significantly enhances detection capability from the NIR to MIR. Additionally， the response time is remarkably reduced from 38 ns to 20 ns. This heterojunction holds great promise for high-speed photodetection in optical communications， LIDAR， photoelectric sensing， and other advanced optoelectronic applications.