Dynamic-scale model tests of a ship anchor chain were conducted to investigate the oscillation of the anchor chain in a chain locker during anchoring. In the tests, the pay-out velocity of the chain was kept constant for a range of speeds 1.0m/s to 2.5m/s. The lateral oscillation and the tension of the ascending chain were measured. The statistical analysis of test data was carried out. Then,resonance phenomena of the chain caused by increasing the pay-out velocity are discussed theoretically. In addition, the effect of the chain pipe length and the upper room height of the chain locker are also described for the purpose of reducing the oscillation. As the results, it is found that the pay-out velocity of the anchor chain, the breadth of the chain locker, the chain pipe length and the upper room height of the chain locker affect lateral oscillation of a chain in a chain locker.