The invention provides a load model building method of considering load frequency characteristics. The method comprises the following steps: obtaining a frequency characteristic curve of a load component; calculating an active power-frequency characteristic coefficient and a reactive power-frequency characteristic coefficient of the load component; dividing the load component into a static load and a dynamic load according to the load characteristic; calculating the active power-frequency characteristic coefficient and the reactive power-frequency characteristic coefficient of the static load; calculating the active power-frequency characteristic coefficient and the reactive power-frequency characteristic coefficient of a load node; and determining a mechanical torque coefficient of an asynchronous motor of the load node. According to the load model building method, the defect that a traditional load model cannot accurately describe the load frequency characteristics is overcome; the simulating calculation credibility of a power system is improved; and a forceful guarantee is provided for scientific planning and safe and stable operation of the power system.