At present, the early diagnosis of cancer is being paid more and more attention.Commonly, the concentration of the cancer cells is extremely low in body fluids, such as circulating blood and sputum, so it is in urgent need of developing cheap, quick and accurate analytical technologies with high sensitivity for the enrichment and detection of rare cells to meet the clinical requirements.In this work, an aptamer-based "sandwich" approach combined with the chemiluminescence (CL) analysis was developed for the capture and detection of rare cells on a microfluidic chip.Aptamers were immobilized on microfluidic channels to achieve capture and isolation of the specific cells from a cell mixture.The capture efficiency for target cells was more than 70% with the purity greater than 97%, when the content of the target cells was between 0.5% and 10% in the initial cell mixture.