Objective To explore the effect of mechanical stimulation on polarity of macrophages. Methods RAW264.7 cells were stimulated with tensile stretch at various amplitude and time, then cell viability was assessed with cell count kit-8 (CCK-8) for determining the stimulation parameters. RAW264.7 cells were induced to M1 type, then tensile stretch at 10% amplitude and 2 Hz was applied to M1 cells. CCK-8 and flow cytometry were used to detect the effects of tensile stretch on cell activity and apoptosis. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the effect of tensile stretch on M1 type macrophage related gene expression. Results After stimulation for 3 hours, tensile stretch at 15% or 20% amplitude and 2 Hz significantly inhibited cell viability (P<0.05), while tensile stretch at 10% amplitude and 2 Hz did not inhibit the viability of RAW264.7 cells (P>0.05). Tensile stretch at 10% amplitude and 2 Hz neither inhibited viability nor cause apoptosis of M1 type macrophages. The expression of inflammation-related genes including interleukin-1β(IL-1β) and tumor necrosis factor-α (TNF-α) of M1 type macrophages was significantly down-regulated with tensile stretch at 10% amplitude and 2 Hz (P＜0.05). Conclusions Mechanical stimulation at 10% amplitude and 2 Hz can inhibit M1 type macrophages and promote the polarization from M1 to M2. Mechanical stimulation may become a method for treating inflammation-related diseases.