Hericerin is an isoindolinone meroterpenoid alkaloid isolated from medicinal mushroom Hericium erinaceum with some bioactivities. Herein, a concise total synthesis of hericerin was described, with four steps and 30% overall yield starting from commercially available methyl 3-hydroxy-5-methoxybenzoate and geranyl bromide. A comprehensive effect of hericerin on HepG2 cell line was observed and confirmed by transcriptomic analysis. Furthermore, hericerin was found to be a new PPARγ agonist.