Glioblastoma multiforme (GBM) is a highly aggressive primary brain tumor associated with limited treatment options and high drug resistance, presenting significant challenges in the pursuit of effective treatment strategies. Epigenetic modifications have emerged as promising diagnostic biomarkers and therapeutic targets for GBM. For instance, histone deacetylase 6 (HDAC6) has been identified as a potential pharmacological target for GBM. Furthermore, the overexpression of monoamine oxidase A (MAO A) in glioma has been linked to tumor progression, making it an attractive target for therapy. In this study, we successfully engineered HDAC-MB, an activatable multifunctional small-molecule probe with the goal of efficiently detecting and killing glioma cells. HDAC-MB can be selectively activated by HDAC6, leading to the "turn on" of near-infrared fluorescence and effective inhibition of MAO A, along with potent photodynamic therapy (PDT) effects. Consequently, HDAC-MB not only enables the imaging of HDAC6 in live glioma cells but also exhibits the synergistic effect of MAO A inhibition and PDT, effectively inhibiting glioma invasion and inducing cellular apoptosis. The distinctive combination of features displayed by HDAC-MB positions it as a versatile and highly effective tool for the accurate diagnosis and treatment of glioma cells. This opens up opportunities to enhance therapy outcomes and explore future applications in glioma theranostics.