Triboelectric nanogenerators (TENGs) efficiently convert low-frequency mechanical energy into electrical energy and are extensively utilized in wearable electronic products. However, when exposed to a wide temperature range environment (10–65 °C) or humid environments, TENGs are confronted with problems such as the temperature drift effect and charge dissipation, which not only compromise human thermal comfort but also restrict their practical application. For this purpose, a multifunctional TENG was designed in this study, featuring both bidirectional thermal regulation and hydrophobic protection. The device employs a thermoplastic polyurethane/tetrabutylammonium hexafluorophosphate (TPU/TBAHP) tree-like nanofiber membrane (TLNM) loaded with polypyrrole (PPy) (PPy@TPU/TBAHP TLNM) as the positive electrodes to enable efficient photothermal conversion. The fluorosilane-modified ZnO nanorods-modified polyvinylidene fluoride (PVDF)/TBAHP TLNM (P-ZnO@PVDF/TBAHP TLNM) were utilized as the negative electrodes to facilitate passive radiative cooling. This TENG can switch flexibly between thermal regulation modes (cooling and heating) in response to ambient temperature, suppressing temperature drift and maintaining human thermal comfort. Meanwhile, it has excellent hydrophobicity (contact angle of 139.2°), which helps to alleviate the problem of charge dissipation in a humid environment. The optimized TENG achieved an output voltage of 98 V and a current of 18.7 μA. Moreover, this TENG demonstrates excellent durability and reliable human motion monitoring capabilities, thus offering a new solution for wearable electronics.