To develop molecular markers for late flowering time in radish we performed QTL-seq analysis in which whole genomes are sequenced and SNPs between two groups showing opposite phenotypes in F2 population are analyzed to find regions or QTLs involved in a trait of interest. Two inbred lines (NH-JS1 and NH-JS2) showing opposite phenotypes of flowering time were selected to generate F2 population for the analysis. NH-JS1 showed late flowering time whereas NH-JS2 early flowering time. Genomic DNA from the two lines were extracted and sequenced. In addition F2 population from F1 between NH-JS1 and NH-JS2 was generated and flowering time phenotypes of 180 F2 plants were analyzed. We selected 11 plants with late flowering time and 12 plants showing early flowering time. We extracted DNA from each individuals from the two groups and bulked them to generate two bulked DNA samples that are subject to whole genome resequencing. Preliminary analysis of SNP data from the resequencing showed that there may be several QTLs involved in flowering time control in radish.