Abstract: The compressive stress experienced by circulating tumor cells (CTCs) in the microcirculation is a key mechanical factor affecting their metastatic potential. This study aims to investigate the independent regulatory effects of compressive stress intensity and duration on cell viability. Referring to the typical diameter of the MCF-7 cell line, microfluidic channels with different widths (9 µm, 12 µm, 15 µm) and lengths (100 µm, 500 µm) were designed to construct an in vitro mechanical stimulation platform, simulating the capillary environment and decoupling the two mechanical parameters. The dynamic process and transit time of MCF-7 cells passing through the microchannels were recorded using high-speed microimaging technology. Fluorescence staining and image analysis were employed to quantitatively evaluate the proliferation and adhesion capabilities of cells after different mechanical stimulations. Results show that the cell transit time is primarily determined by the channel length, while a decrease in channel width increases the dispersion of transit velocities. Regarding cell viability, under short-duration compressive stimulation (approx. 3 ms), cell proliferation ability decreased with increasing stress intensity; whereas under long-duration stimulation (approx. 15 ms), it showed a trend of first enhancing and then weakening. Furthermore, compressive stress significantly inhibited cell adhesion ability, and the effect was more pronounced with prolonged stimulation. This study provides support for deciphering the regulation of cell fate by stress stimulation intensity and time, offering experimental evidence for a deeper understanding of the metastasis mechanism of circulating tumor cells.