The Fourier series loading model is extracted from 1 407 continuous induced-loading curves traced with a microelectronic mechanical system (AH100B sensor) when 201 pedestrians are walking on the floor. First, the three-axis acceleration of carrier coordinate system is converted to natural coordinate system using attitude matrix formed by attitude angle. The dynamic load factors and phase angles in longitudinal, lateral and vertical direction of the first four orders are calculated using the Fast Fourier Transform to obtain the three-dimensional Fourier series loading models to solve the problem of structural vibration serviceability. Then, a single load time-spectrum plot is gained using the wavelet transform to reflect the variability of frequency during human walking. Finally, comparisons with the existing loading models prove that the proposed model is reasonable and feasible which can be provided for designers to design and analysis, especially for in the case of large span structures considering human excited vibration problems.