A child seat attachment structure comprising a lower anchor comprising a fixing portion that is fixed to a configuration member configuring a vehicle body or a vehicle seat, a leg portion that extends from the fixing portion towards a vehicle top side, and a coupling portion that is provided at an upper end portion of the leg portion and that fixes a child seat to the vehicle body or the vehicle seat by connecting to a connector of the child seat; and a contacted portion that restricts displacement of the coupling portion of the lower anchor towards a vehicle front side with respect to the fixing portion by making contact with a portion of the lower anchor when the child seat fixed to the vehicle body or the vehicle seat has moved towards the vehicle front side.