This study aims to develop sulforaphane-loaded gold nanoparticles (SFN-GNPs) as a potential nanomedicine against the solid tumors. Citrate-mediated electrolysis optimized by four-factor three-level Box-Behnken experimental design was used to get nanoparticles of size <200 nm. The formulation was characterized and evaluated for cytotoxicity B16-F10, MCF-7, SW-620 and Caco-2 cell line. Single dose oral pharmacokinetics, gamma scintigraphy-based bio-distribution and tumor regression studies were conducted to evaluate the in vivo performance. Optimized SFN-GNPs showed spherical morphology with a particle size of 147.23 ± 5.321 nm, the zeta potential of -12.7 ± 1.73 mV, entrapment efficiency of 83.17 ± 3.14% and percentage drug loading of 37.26 ± 2.33%. With SFN-GNPs, both SFN (75.99 ± 2.36%) and gold (58.11 ± 2.48%) were able to permeate through the intestinal wall in 48 h. SFN-GNPs were able to bring LC50 of <100 µg/ml in all the cytotoxicity assays, more than 5-fold increase in AUC0-t, enhanced retention at tumor site as well as significant pre-induction tumor growth inhibition and post-induction tumor reduction as compared to plain SFN solution.