Glycogen synthase kinase-3 beta (GSK-3β) is a multifunctional serine/threonine kinase mediating multiple cellular functions, such as differentiation, apoptosis, and cell proliferation. Because of their ability to alter carcinogenic pathways, GSK-3β inhibitors are being explored for the development of anticancer molecules. In the present study, we synthesized and evaluated the cytotoxic properties of a series of twenty indole–triazole-linked pyrazolone derivatives, 10Aa–Ed. All derivatives were characterized by FTIR, ¹H/¹³C NMR, and high-resolution mass spectrometry (HRMS) methods. All compounds and standards, sunitinib and 5-Fluorouracil (5-FU), were screened against four adherent cell lines, including pancreatic adenocarcinoma (Capan-1), colorectal carcinoma (HCT-116), glioblastoma(LN229), and lung carcinoma (NCI-4460), and four non-adherent cell lines, including acute myeloid leukemia (HL-60), chronic myeloid leukemia (K562), T lymphoblast (MOLT4), and non-Hodgkin lymphoma (Z138). Among the screened derivatives, molecule 10Aa showed cytotoxicity against MOLT 4, Z138, and HL60 with CC₅₀ values of 14.45 μM, 15.34 μM, and 17.56 μM, respectively. GSK-3β kinase inhibition was evaluated with the 10Aa, which is capable of inhibiting GSK-3β in a dose-dependent manner. Additionally, molecular docking was performed to estimate the correlation between invitro data and GSK-3β binding affinity. The outcomes of the invitro experiments demonstrated strong concordance with the insilico data. The discovery yielded compounds 10Aa and 10Cd, which can be modified to create effective anticancer agents that target GSK-3β.