A portable pet bed apparatus is provided that can be selectively side mountable to a bed assembly. The pet bed apparatus includes a carrier device that defines a bedding space thereof sized and dimensioned to accommodate a domestic pet therein. The pet bed apparatus further includes a mounting assembly having a horizontal portion and a vertical portion that lies closely adjacent to the bed assembly, and a connector assembly on the side of the carrier device for detachably connecting the carrier device to the vertical portion of the mounting assembly. The carrier device can be removed from the mounting assembly, which enables independent functionality as a pet carrier.
