In this study, we present a novel ultraviolet-visible/fluorescent dual-output sensing platform for the multiplexed detection of microRNAs (miRNAs) in tumor cells. For the first time, carbon dots (CDs) were synthesized from Tremella via a one-step hydrothermal process and integrated with poly(A)-functionalized gold nanoparticles (AuNPs) and DNA nanohooks generated through hybridization chain reaction (HCR). In the absence of target miRNA, HCR triggers the formation of DNA nanohooks, leading to AuNP aggregation and a visible color change from red to colorless, while the CDs emit strong fluorescence. Upon target binding, HCR is inhibited, preserving AuNP dispersion and causing fluorescence quenching due to CD-AuNP proximity. This dual-signal response enables reliable, background-minimized detection. By simply altering the recognition sequences, the platform allows simultaneous detection of multiple miRNAs, such as miR-222, miR-21, and miR-122. The use of Tremella-derived CDs offers a sustainable, biocompatible alternative to conventional fluorescent materials. This platform demonstrates excellent sensitivity, specificity, and versatility, showing great potential for miRNA-based cancer diagnostics and high-throughput clinical analysis.