With the rapid development of flexible electronics and smart wearable technologies, traditional single-function flexible sensors are difficult to meet the complex and variable practical needs. The multimodal sensing has emerged as a key development trend in flexible sensors. In this study, a polyacrylamide-polyvinyl alcohol‑lithium chloride (PAM-PVA-LiCl) hydrogel is synthesized, which exhibits excellent tensile strength (600.11 %) and high ionic conductivity (2.56 ± 0.20 S/m). This hydrogel is used as an electrode, while polydimethylsiloxane (PDMS) is employed as both the encapsulation and triboelectric layer to fabricate a single-electrode flexible triboelectric nanogenerator (TENG). When the hydroxypropyl methyl cellulose-polyethylene glycol‑cobalt chloride (HPMC-PEG-CoCl 2) film serves as the triboelectric material, the TENG achieves a maximum instantaneous power density of 176.92 mW/m 2 and an average power density of 6.14 mW/m 2. A dual-modal sensing system is developed based on this TENG, which has sensitivities of 16.3906  V/mm (from 0 mm, serving as the contact reference for non-contact distance sensing, to 10 mm), 2.6873 V/mm (10 mm to 30 mm) for non-contact distance, and 1.4151 V/% RH (10 % RH-70 % RH) for humidity sensing, respectively. This dual-modal sensing system holds significant promise for addressing the challenges of sensor adaptability in intricate settings, facilitating sophisticated integration in applications like intelligent monitoring, and opening the door for future innovations in flexible sensing technology.