High-density genetic linkage map plays an important role in genome assembly and QTL fine mapping. Since the coming of next-generation sequencing (NGS), makes the structure of high-density linkage maps much more convenient and practical, which simplifies SNP discovery and high-throughput genotyping. In this research, a high-density linkage map of cucumber was structured using specific length amplified fragment sequencing, using 153 F2 populations of S1000×S1002. The high-density genetic map composed 3,057 SLAFs, including 4,475 SNP markers on 7 chromosomes, and spanned 1061.19cM. The average genetic distance is 0.35cM. Based on this high-density genome map, QTL analysis was performed on two cucumber fruit traits, fruit length and fruit diameter. There are 15 QTLs for the two fruit traits were detected.