In this paper we are presenting a design of isosceles trapezium shaped polysilicon cantilever beam at Micro Electro Mechanical Systems (MEMS) level that is highly sensitive for extreme low pressure measurements. Using surface micromachining technique, the design concentrates on optimizing the shape of the rectangular and triangular beam so that the final design provides tradeoff between sensitivity and maximum tolerable pressure. For the applied pressure, this paper concentrates a Finite Element Analysis (FEA) on beam's displacement, distribution of stress along its length using Intellisuite software simulation tool for the trapezoidal cantilever beam. The analysis is also extended to find the maximum tolerable pressure for the trapezoidal beam. © 2006-2016 Asian Research Publishing Network (ARPN). All rights reserved.