Malignant brain tumors remain a major cause of concern and mortality as successful treatment is hindered due to the poor transport and low penetration of chemotherapeutics across the blood–brain barrier (BBB). In this study, a nano formulation composed of chlorotoxin (CTX)-conjugated morusin loaded PLGA nanoparticles (PLGA–MOR–CTX) was devised against Glioblastoma Multiforme (GBM) and its anti-proliferative effects were evaluated in vitro. The synthesized nanoparticles were loaded with morusin, a naturally derived chemotherapeutic drug, and surface conjugated with CTX, a peptide derived from scorpion venom, highly specific for chloride channels (CIC-3) expressed in glioma tumor cells, as well as for matrix metalloproteinase (MMP-2), which is up regulated in the tumor microenvironment. Subsequently, the anti-cancer potential of the NPs was assessed in U87 and GI-1 (human glioblastoma) cells. Antiproliferative, cell apoptosis, and other cell-based assays demonstrated that the PLGA–MOR–CTX NPs resulted in enhanced inhibitory effects on U87 and GI-1 glioma cells. Prominent cytotoxicity parameters such as ROS generation, enhanced caspase activity, cytoskeletal destabilization, and inhibition of MMP-activity were observed in glioblastoma cells upon PLGA–MOR–CTX NP treatment. The cytocompatibility observed with normal human neuronal cells (HCN-1A) and the enhanced lethal effects in glioblastoma cells highlight the potential of PLGA–MOR–CTX nanoparticles as promising therapeutic nanocarriers towards GBM.