The invention discloses an obese receptor (OB) gene and application thereof as a goose fat character genetic marker. Genetic markers in the OB gene relevant to goose abdominal fat weight and abdominal fat rate are determined, and the polymorphism in the OB gene in a nucleic acid sample obtained from a goose is determined and causes that the coded amino acid changes and is relevant to the abdominal fat weight and the abdominal fat rate. According to the single nucleotide polymorphism of the OB gene, animals containing the OB genes in a genome DNA are subjected to fatty breeding, and protogene types reducing the abdominal fat weight and abdominal fat rate of the goose are screened, thus the OB gene has important application value and economic benefit.