Monitoring deep wounds is challenging but necessary for high-quality medical treatment. Current methodologies for deep wound monitoring are typically limited to indirect clinical symptoms or costly non-real-time imaging diagnosis. Herein, a smart system is proposed that enables in situ monitoring of deep wounds' status through a semi-implantable device composed of 2 seamlessly connected functional components: 1) the well-designed, microchannel-structured sampling needles that efficiently and conveniently collect samples from deep wound anatomical locations, and 2) the multiplex biochemical testing compartment that facilitates the immediate and persistent detection of multiple biochemical indicators based on a color image processing software accessible to a conventional smartphone. With the 3 representative preclinical deep wound models, the study demonstrates the device's potential to monitor wound infection, inflammation, healing progress, and reduce inflammation when applied to deep skin injury, surgical implantation, and postoperative intestinal leakage. The device's capability to rapidly and accurately identify pathogenic bacteria is also demonstrated both in vitro and in vivo, potentially facilitating precise intervention in infected wounds. Coupled with the device's favorable biocompatibility and cost-effectiveness, this intelligent system emerges as a promising tool for safe and effective management of complicated deep wounds.