A vertical pet excrement collection device. The device is an absorbent fabric collecting sheet mounted on a frame and maintained in a substantially vertical orientation to catch pet excrement emitted that would not land on or be absorbed by a horizontal collection device. In one embodiment, the device is incorporated with and connected to an existing horizontal collection device such as a litterbox. In a second embodiment the collection device is a frame on which an absorbent sheet is mounted, the frame having an interconnected horizontal frame and vertical frame defining a horizontal pad and a vertical pad. Simple and quick removal and replacement of the absorbent material is provided so that a solid sheet may be easily replaced.