Proposed are a method and device for acquiring information on links between MLDs in a wireless LAN system. Specifically, a receiving MLD transmits a probe request frame to a transmitting MLD through a first link. The receiving MLD receives a probe response frame from the transmitting MLD through the first link. The transmitting MLD comprises: a first transmitting STA operating in the first link; a second transmitting STA operating in a second link; and a third transmitting STA operating in a third link. The receiving MLD comprises a first receiving STA operating in the first link. When the first receiving STA requests for information on the second and third links, the probe request frame includes link identifiers for the second and third links. When the first receiving STA requests for information on all the links, the probe request frame does not include link identifiers for all the links.