Wheat is one of the most important food crops in the world. Genetic improvement of its quality traits is one of the research hotspots. Protein-related traits such as grain protein content, wet gluten content and sedimentation value have important effects on wheat grain quality. In this study, a F6 recombinant inbred line (RIL) population derived from the cross of Avocet and Chilero. Phenotypic data were collected of protein content and wet gluten content in four environments and sedimentation values were collected in three environments. It was found that there was a significant positive correlation between protein content, wet gluten content and sedimentation value. Utilizing a Wheat 55K SNP array, a high-density genetic linkage map spinning 3859.32 cM was constructed. QTL mapping showed that 25 QTLs were detected for 3 traits, and they were distributed on chromosome 1B, 2B, 3A, 3D, 4D, 5D, 6A, 6B, 7A and 7D. These QTLs individually explained 3.72%-23.59% of the phenotypic variation with LOD values ranging from 2.77 to 8.37. Among them, four major QTLs for GPC located on chromosomes 2B, 3A, 5D, 6A were detected under two or more environments, which could explain 10.56%-23.59% of the phenotypic variation. For WGC, five major QTLs were detected under two or more environments, which were mapped to chromosomes 1B, 2B, 5D and 6A, respectively, explaining 10.49% to 18.80% of phenotypic variation. For SV, three major QTLs located on chromosomes 3A, 6A and 7A were detected, which could explain 10.20%-15.58% of phenotypic variation. Meanwhile, it was found that three QTL clusters were located on chromosomes 2B, 3A and 5D, respectively. The pleiotropy locus QGPC.haust-2BL was screened for candidate genes, which contained 603 high confidence genes, including 28 protein-related candidate genes. Among them, 5 candidate genes are mainly associated with ubiquitins, which may mediate the degradation of specific proteins through the ubiquitin-proteasome pathway and regulate protein concentration in grains. The five candidate genes are TraesCS2B03G1479100, TraesCS2B03G1480300, TraesCS2B03G1480500, TraesCS2B03G1492500 and TraesCS2B03G1504000. This study provides an important base for protein-related traits QTL (gene) cloning in wheat and lays a theoretical foundation for marker-assisted breeding and Biofortification molecular breeding.