Circulating tumor cells (CTCs) and circulating tumor microemboli (CTM) are rare cell species present in peripheral blood and appear in circulatory system during cancer metastasis. As phenotype of single or aggregated CTCs can be different and may present different levels of potential aggressiveness, detecting and capturing both of them are crucial for preventing recurrence as well as achieving early-stage diagnosis. This research presents a microfluidics system aiming at isolating and highly sensitive capturing of CTCs and CTMs. A serpentine channel and a series of bifurcating micro-channels were use to separate CTCs and CTMs from other blood cells. A graphene oxide interface was patterned on glass slide to facilitate antibodies conjugation via click chemistry for capturing CTCs and CTMs, thus achieving multiplex detection in a high specificity and bio-compatibility manner.