In order to investigate whether miR-675-5p exhibit its oncogenic role via regulating RalBP1/RAC1/CDC42 pathway by targeting REPS2 in ESCC, we examined the expression of downstream target genes in REPS2 signaling pathway and found that the expression of RalBP1, RAC1, CDC42, MMP9, MMP2 and CyclinD1 were decreased in ESCC cells that stably down-regulated miR-675-5p. The gene discussed is CDC42; the disease is esophageal squamous cell carcinoma.