Ganoderma applanatum is a widely distributed saprobic or parasitic mushroom, it was found at the bases of decaying logs in Hakozaki Higashi-ku Fukuoka-shi. Japan. The mushroom was extracted with 80% methanol, and LC-HRMS analysis was conducted to illustrate the bioactive ingredients. The cytotoxicity of the total metabolite extract was evaluated against human colon cancer cell line (Caco-2) which showed IC₅₀ value of 160 ± 4.08 μg/ml. G. applanatum methanolic extract caused different morphological alterations and increased glutathione level in the treated cells. Interestingly, G. applanatum increased Bax/Bcl-2 ratio significantly (P ˂ 0.05) at concentrations of 80 and 160 μg/ml on Caco-2 undergoing apoptotic p53-independent pathway with lake expression of p53 protein and up-regulated Cas-3 mRNA. The in vivo study on solid Ehrlich tumor (SEC) revealed a decrease in the volume of the developed tumor mass after five days of G. applanatum (200 μg/ml) treatment. The apoptotic p53-dependant pathway was confirmed by mRNA Bax/Bcl-2 increased ratio in addition to p53 and Cas-3 up-regulation. In conclusion, G. applanatum could exert apoptotic antitumor properties in Caco-2 by p53-independent pathway and p53-dependant in SEC. The findings proved that G. applanatum can be a promising candidate as alternative or co-anticancer medications.