Objective To analyze the motion, deformation, and adhesion behavior of circulating tumor cells (CTCs) in bifurcated microvessels, reveal their mechanical properties under different flow conditions and explore their role in the process of cancer metastasis. Methods A cell-scale modeling approach was adopted, combining the immersed boundary-lattice Boltzmann method (IB-LBM) and the adhesive-dynamics model to simulate the motion and adhesion behavior of circulating tumor cells in microvessels. Results The adhesion behavior of CTCs was significantly influenced by the Reynolds number (Re) and the surface elastic moduli of cells. Under the condition of Re=0.003, the adhesion behavior of CTCs was the most stable; CTCs with a lower surface elastic modulus exhibited greater deformation during adhesion and demonstrated stronger adhesive forces. Conclusions The mechanical properties of CTCs and flow field conditions jointly determine their transport and adhesion behavior in microvessels. The levels of Re and surface elastic modulus play a critical role in the deformation and adhesion of CTCs. The study of the adhesion characteristics of CTCs provides mechanistic insights and new potential directions for cancer prevention and treatment research.