The invention discloses function candidate gene for affecting the meat quality trait of a pig and a screening method of t function candidate gene. The function candidate geneisRXRG, GPI, CPT2 and/or GABARAPL1. The screening method comprises the following steps: (1), selecting longissimus muscles of two extreme pig breeds with large meat quality trait difference, extracting DNA, and independently creating databases; (2), performing whole genome DNA methylation sequencing on sample DNA databases by adoptingan MeDIP-Seq technology; (3), obtaining maps of whole genome DNA methylation levels of the two extreme pig breeds, and screeningdifferentialmethylationexpressed genes; (4), performing GO functional annotation and KEGG Pathway analysis on the differentialmethylationgenes, and screening out functional genes and regulatory pathways related to meat quality traits, such as fatty acid formation and decomposition; (5), performing DNA methylation and expression profileconjoint analysis through MeDIP-seq and RNA-seqtest results, and obtaining the function candidate gene of the meat quality trait of the pig. According to the method, the function candidate geneparticipatinginregulationof the meat quality trait of the pig is screened out, and a foundation is laid for the future deep research.