This paper reports a detailed analysis on the effect of damping on the performance of AlN contour mode resonator (CMR) sensors. Microelectromechanical systems (MEMS) resonant sensors give high sensitivity and resolution owing to miniaturization of the device size. Especially, AlN contour mode resonators (CMRs) demonstrate outstanding limit of detection (LOD) for mass and magnetic field sensing while consuming very low power. However, there are unintended energy fluctuations within AlN-CMRs, which directly impact the device performance. Although, such unwanted energy fluctuations would drastically degrade the performance of AlN-CMRs, minimizing the damping and thus achieving high quality factor (Q) could compensate these adverse performances. In this work, we model and simulate the mechanical and thermoelastic damping to develop an optimal AlN resonant sensor designs for mass sensing and gas detection purposes. In more detail, we analyze which damping mechanism is more dominant for specific target applications. Our preliminary findings indicate that various parameters (i.e. device size, number of fingers, operating frequency, and excitation orientation) of resonators directly impact the amount of damping and should be considered when designing AlN resonant sensors.