Updated project metadata. Since the effect of selection for better feed efficiency on meat characteristics is largely unknown. Thus, the aim of this study was to identify key proteins and pathways regulating both FE traits and meat characteristics. At ten weeks of age, thigh muscle samples from six birds (three with high FCR and three with low FCR value) were selected, and their proteomes were investigated using a label-free proteomic method. Weighted gene co-expression network analysis (WGCNA) was used to screen the key protein modules and pathways. We found that glycolysis/gluconeogenesis, metabolic pathway, carbon metabolism, biosynthesis of amino acids, pyruvate metabolism, and protein processing in endoplasmic reticulum play a key role underlying these two traits. Thus, selection practices for KR should simultaneously consider both trait groups to maintain the high meat quality of slow-growing chicken while improving FE.