The invention relates to the technical field of polling of field buses, and relates to a shared bus polling method and device based on a collaborative multi-task scheduling mechanism, wherein the polling method comprises the following steps of: comparing the priorities of online slave equipment; and, according to a priority comparison result, selecting the slave equipment having the highest priority to occupy a bus to perform data interaction, and, enabling the corresponding slave equipment to be dormant after data interaction is completed. By means of the method, the priorities are distributed to various equipment and commands; the equipment polling period is dynamically adjusted; therefore, data of the equipment having the high priority can be responded in time; furthermore, the problem that the equipment having low priority completely cannot be processed when data of the equipment having the high priority is busy can be avoided; the problem that response of a control command is overtime can be solved; and in addition, the data change response problem of the important equipment when the number of the slave equipment is gradually increased can be solved.