A nanometer-sized graphene pressure sensor is schematically proposed. The graphene membrane is placed over a square cavity etched onto SiO2 substrate so that the transport is along the armchair direction of the graphene. Two contacts are considered at two ends of the device. Current-pressure characteristic is obtained for various cavity sizes, bias voltages, and temperatures. The device behavior is investigated in terms of sensitivity and linearity error. For sensorswith 30 × 30 nm2 cavity size, at room temperature, the sensitivity of 2300 pA/A/Pa and linearity error of 1.042% are obtained. The temperature dependent behavior of the proposed device is also investigated. Mechanical behavior is simulated by means of geometric nonlinear analysis and clamped boundary conditions along all sides of the graphene membrane. Electronic simulations are carried out by means of NEGF-tight-binding formalism.