Development of pressure sensors for harsh environments with high pressure, humidity, and temperature is essential for many applications in the aerospace, marine, and automobile industries. However, existing materials such as polymers, adhesives, and semiconductors are not suitable for these conditions and require materials that are less sensitive to the external environment. This studyproposed a pressure sensor that could withstand harsh environments and had high durability and precision. The sensor comprised apiezoresistor pattern and an insulating film directly formed on a stainless-steel membrane. To achieve the highest sensitivity, a patterndesign method was proposed that considered the stress distribution in a circular membrane using finite element analysis. The manufacturing process involved depositing and etching a dielectric insulating film and metal piezoresistive material, resulting in a devicewith high linearity and slight hysteresis in the range of a maximum of 40 atm. The simplicity and effectiveness of this sensor renderit a promising candidate for various applications in extreme environments.