The invention discloses a pet feeder, which comprises a food containing chamber and a food leaking area, wherein the food containing chamber is jointly defined by a first shell and a second shell, a first edge is formed on the first shell and a second edge is formed on the second shell; the food leaking area is formed between the first edge and the second edge; and the first shell and/or the second shell comprise a base wall and a retractable wall which is connected with the base wall and can extend and retract relative to the base wall, the states of the food leaking area comprise a common state and a retracted state, and the gap of the food leaking area in the retracted state is larger than the gap of the food leaking area in the common state. The pet feeder has the advantages that the adding of pet food is facilitated and much food can be added at one time; and the exaltation of the interest of a pet in playing the pet feeder is facilitated and the intelligence cultivation of the pet is facilitated.