Ferroptosis-an iron-dependent form of cell death triggered by phospholipid peroxidation-has emerged as a promising therapeutic avenue in cancer treatment. Although neuroblastoma (NB) has been identified as a ferroptosis susceptible cancer, our studies reveal striking heterogeneity in ferroptosis sensitivity across high-risk NB models. Through a targeted metabolic compound screen, we identified stearoyl-CoA desaturase 1 (SCD1)-a key enzyme in monounsaturated fatty acid (MUFA) synthesis-as a robust ferroptosis-sensitizing target. Genetic and pharmacological inhibition of SCD1 restored ferroptosis sensitivity in resistant NB cells. Notably, high SCD1 expression correlates with poor patient prognosis. Co-treatment with arachidonic acid (AA), a polyunsaturated fatty acid (PUFA), further enhanced ferroptotic cell death via increased PUFA/MUFA ratio. Nevertheless, neither baseline lipidomic profiles nor transcriptomes of key ferroptosis regulators reliably predicted ferroptosis sensitivity. To overcome AA's poor solubility, we engineered AA-loaded lipid nanoparticles (AA-LNPs), which selectively accumulated in high-risk NB tumors and synergized with SCD1 inhibition. This dual-sensitization strategy, termed LipidSens, significantly suppressed tumor growth and induced ferroptosis in cell-derived xenograft mouse models without systemic toxicity. Together, these findings establish MUFA synthesis blockade and PUFA enrichment as a tumor-targeted, ferroptosis-enhancing strategy, and offer a nanomedicine-based therapeutic platform for high-risk NB.