The medicinal fungus Ganoderma lucidum is rich in bioactive triterpenoids and polysaccharides. The complexity and adaptive resistance of lung cancer necessitate therapeutic strategies that simultaneously disrupt multiple oncogenic pathways. We employed a systems pharmacology approach that integrates network analysis and artificial intelligence to elucidate the multitarget anticancer mechanisms of G. lucidum compounds. Bioactive metabolites were screened, and their targets were integrated with lung cancer-associated genes to construct a compound-target-pathway network. AI-based molecular docking validated key interactions. The top-predicted multitarget compounds were functionally validated in H1299 nonsmall cell lung cancer cells using viability, migration, and Western blot assays. A network of 67 synergistic targets, including PIK3CA, STAT3, EGFR, and TP53, concurrently modulates proliferation, apoptosis, and immune evasion pathways. Triterpenoids, such as lucidumol A and ganoderic acid A, act as key drivers capable of binding multiple signaling hubs. These metabolites and a standardized G. lucidum extract synergistically disrupt oncogenic signaling by inhibiting cell proliferation (extract IC₅₀ = 1669 μg/mL), suppressing migration, and reducing STAT3 phosphorylation and c-Myc expression. These fungal metabolites exhibit potent multitarget tumor-suppressive properties.