Disclosed in the present invention are a method and an apparatus for determining resource occupation state. The method comprises: a first node receiving SA information sent by at least one second node, the SA information being used for indicating resource occupation state of the second node; at each state maintenance moment, the first node determining, according to the service transmission cycle of the first node itself and the SA information, the resource occupation state within the state maintenance cycle which has a length of the service transmission cycle of the first node The solutions provided in the embodiments of the present invention can effectively support the sensing of the resource occupation state in various service transmission cycles, and reduce the complexity of resource occupation state maintenance and resource selection.