Micro-mass sensors have attracted increasing attention in the fiel of biomolecular and chemical detection. It has been found that the size, shape, and geometry of the structure may affect the performance of the sensor. As a result, a topology optimization methodology is proposed in this paper for the design of micro-mass sensors. A phasefiel function controlled by nodal variables and finit element shape functions is used to describe the configuratio of a sensor in the constructed optimization problem. The design goal is to maximize the mass detection sensitivity. On the basis of these formulations, an optimization algorithm is constructed using the finit element method and the method of moving asymptotes. Numerical examples are presented to demonstrate the validity of the proposed problem formulation. The results suggest that the performance of the micro-mass sensor can be improved by using the proposed approach. Micro-mass sensors have attracted attention in the fiel of biomolecular and chemical detection. It has been found that the size, shape, and geometry of the structure may affect the performance of the sensor. As a result, a topology optimization methodology is proposed in this paper for the design of micro-mass sensors. A phasefiel function controlled by nodal variables and finit element shape functions is used to describe the configuratio of a sensor in the constructed optimization problem. The design goal is to maximize the mass detection sensitivity. On the basis of these formulations, an optimization algorithm is constructed using the finit element method and the method of moving asymptotes. Numerical examples are presented to demonstrate the validity of the proposed problem formulation. The results suggest that the performance of the micro-mass sensor can be improved by using the proposed approach.