Abstract: The parallel-plate flow chamber (PPFC), of which the height is far smaller thanits own length and width is one of the main apparatus for the in vitro study of the mechanical behaviors of cultured cells at the bottom of PPFC undergoing shear stress.The PPFC of which the upper and lower plates are rectangular is usually used by research workers. and the flow field in this kind of PPFC (exeept for the regions near the entrance and exit is unifrom[1], so only the effect the shear the shear stress with one value has on cultured cells can be observed during each experiment .A kind of of PPFC of which the upper and lower plates are not rectangular is proposed in this paper. The distributions of the velocities inside and the shear stresses at the bottom of the chamber are given by analyzing the flow field of the steady flow in the PPFC. Theresults show that the mechanical behaviors of cultured cells undergoing the shearstresses with various values may be simultaneously observed by the use of this kind of irreclangular PPFC. The theoretical and experimental results obtained by Ultrasonic Doppler Technique show good agreement.