Objective To investigate the influence of thrombus entrance shape, suction rate and blood flow velocity on thrombus aspiration of rotary cutting and suctioned thrombectomy devices, so as to provide theoretical support for the design and optimization of such devices. Methods Three models with different thrombus entrance shapes (‘L’-style, ‘8’-style and ‘0’-style) were established to study the influence of thrombus entrance shape on the thrombectomy; different suction rates (75, 100, 125, 150 mL/min) and different blood flow velocities (0-10 cm/s, at interval of 1 cm/s) were set to discuss how the suction rate and blood flow velocity affected the thrombectomy based on ‘8’-style thrombus entrance. Results The thrombus could not be aspirated evenly in ‘L’-style model, and there was no significantly difference in aspiration between ‘8’ -style model and ‘0’-style model. But the ‘8’-style model was better than ‘0’-style model in lateral thrombus suction. The suction rate that was greater than 100 mL/min provided a limited effect on improvement of thrombectomy effect. The best suction effect was reached when blood flow velocity was less than 1 cm/s, and the effect of thrombectomy was decreasing gradually with blood flow velocity increasing. Conclusions The thrombus entrance shape, suction rate and blood flow velocity had a great impact on thrombectomy greatly. A wide and short thrombus entrance shape, an appropriate increase of suction rate and decrease of blood flow velocity would contribute significantly to the improvement of thrombectomy effect. These results can be used as guidance for the optimal design of rotary cutting and suctioned thrombectomy devices.