PROBLEM TO BE SOLVED: To provide a drinking vessel for a pet which can be carried together with a PET resin-made vessel, and enables a dog or the like to easily have a drink or the like.SOLUTION: The drink vessel 1 for a pet attachable to a 500 ml PET bottle PB used for a commercial beverage includes: a bond part 13 having an approximately cylindrical inner surface for a drinking opening 71 of the PET bottle to be screwed to or for an accessory cap screwed to the drinking opening to be inserted in for integration with the PET bottle a shell-like bowl part 11 capable of accommodating a liquid material in the inside and letting one end of the bond part open in the inside and an expansion part 12 continuing to a part of the bowl part on a virtual plane B-L perpendicular to the axis of the bond part and expanding in the direction of getting distant from the bond part to have a recess on the axis side, on one division made by dividing the expansion part with a virtual plane H-J containing the axis of the bond part.COPYRIGHT: (C)2010,JPO&INPIT【課題】PET樹脂製容器と一体に携行することができ、犬等が飲料等を飲みやすいペット飲用容器を提供する。【解決手段】市販飲料に使用される500mlPETボトルPBに取付可能なペット飲用容器1であって、PETボトルの飲み口71を螺合させて、または飲み口に螺合させた付属キャップを嵌入させてPETボトルと一体化させるための、内面が略円柱状である結合部13と、内側に液状物を収容可能であって内側に結合部の一端を開口させる殻状の椀部11と、結合部の軸心を含む仮想平面H-Jで2分された一方の側において結合部の軸心に直交する仮想平面B-L上で椀部の一部に連続し結合部から遠く離れる方向に拡がって軸心側が凹状である拡張部12と、を有する。【選択図】 図1