Abstract: Based on the idea of fully combining the three components of fluctuating wind-induced response (background, resonant and their coupling term), a method for determining the characteristic of fluctuating wind-induced response of large-span roofs is proposed, which is used to calculate the fluctuating wind-induced response accurately and efficiently. The concept of strain energy is introduced, and the contributions of each fluctuating wind-induced response component to the total response at all structural nodes are considered and the strain energy prediction coefficients of each response component are defined. In order to avoid directly calculating the specific value of each response component, the expression of each response component is simplified according to the characteristics of the transfer function and wind load spectrum of each response component, so that the strain energy prediction coefficients could be obtained by a few wind load parameters and structural dynamic characteristic parameters. According to the value of strain energy prediction coefficients, the characteristic categories of fluctuating wind-induced response of large-span roofs are divided into I-VI; on this basis, the combining principle for the total fluctuating wind-induced response is developed. Taking the Lotus court roof as an example, the characteristic type of fluctuating wind-induced response is determined and the total fluctuating wind-induced response is obtained. The results indicate that the proposed method can determine the characteristic type of fluctuating wind-induced response conveniently, and the combined total response is in good agreement with the accurate value.