A pet collar structure includes a collar body and an elastic connecting member. The collar body includes beads, a first magnetic fastener and a second magnetic fastener. The first magnetic fastener and second magnetic fastener are detachably magnetically attracted to each other. The elastic connecting member includes a first sleeve portion and a second sleeve portion. The first sleeve portion sleeves the collar body and is positioned neighboring to the first magnetic fastener. The second sleeve portion sleeves the collar body and is positioned neighboring to the second magnetic fastener. With the coordination of the first magnetic fastener, the second magnetic fastener and the elastic connecting member, the collar body is worn on a neck of a pet. When the pet runs, scratches or shakes, with the elastic extension and elastic retraction of the elastic connecting member, the collar body is kept from falling off, hence achieving wearing stability.