Abstract: A 100 MeV proton cyclotron, referred to as CYCIAE-100, is designed to provide proton beams with energy up to 200 A. When the cyclotron is under commissioning, a beam dump is required to measure the beam with a power of 20 kW. The paper introduces the beam line, target material selecting, target configuration, cooling calculation and the local shielding structure. The calculation result of the beam line matching is given. After comparing the neutron yield, flux angle and thermal activation of the targets of different materials by the proton targeting, the aluminum is selected as the target material. Based on the extraction beam energy and power of the cyclotron, a layered target configuration is designed, and the cooling calculation result is presented. The average energy of the emergent particle produced by the proton targeting is relatively high, so it will produce large radiation dose. Considering the harmful effect on the environment and personnel, the local shielding is selected for use. The calculation result and configuration of the local shielding are also presented in the paper.