We develop a novel multilayer concentric filter device conjugated with an immune-binding method to achieve enrichment and detection of rare cells in a mass cell population by size based separation. Filter and size-based separation is one of the most efficient, simple and inexpensive method to isolate cells, but it encounters main disadvantages of clogs, cell deformation and insignificant size difference between targeted cell and normal cell. The concentric filter device and method used in this research were designed to create significant size difference and better separation efficiency by clogs reducing to identify rare cell with simple lab instrument. The target rare cells enrichment and detection from a mass cell population is successfully demonstrated by mixing 1:100,000 ratio of targeted MCF-7 and Jurkat cell. The device can be potentially applied for clinical Circulating Tumor Cells (CTCs) detection in the future.