In order to understand the genetic basis of silk color in maize, the candidate genes and excellent alleles associating with silk color were explored. The recombinant inbred lines (RIL) crossed from maize cultivars “Zheng 58” and “Chang 7-2” were used for QTL mapping. A fine mapping of the major gene qSC10 causing pink silk was conducted in a F3 population of “Zheng 58” that hybridized with a near isogenic line qSC10-NIL (harboring qSC10), followed by a physical mapping and candidate gene analysis according to the reference genome sequence of B73 (RefGen-v4). Four major QTL were identified on chromosomes 1, 8, 9 and 10 using the RIL families, and each explained 3.34% to 12.28% phenotypic variation. The gene qSC10 on chromosome 10 was delimited to a 374.2 kb interval which contains 14 annotated genes, including the R-S gene (GRMZM5G822829) that was associated with seed coat color. The R-S gene was found to be expressed in silk, root, leaf and tassel, while the expression level of qSC10-NIL in silk was significantly higher than that of Zheng 58. Collectively, these results suggested that the R-S gene, which is a candidate gene for qSC10, may contribute to the accumulation of anthocyanins in maize filament by a positive regulation on the expression of anthocyanin synthesis-related genes.