Hydrate plugging is an important factor affecting the safety and efficiency of flow assurance. Current prevention methods for hydrate plugging are costly or environmentally unfriendly or inefficient. In this work, an efficient method to prevent hydrate plugging during deep-water gas well testing was put forward, which is achieved by reasonably changing the testing orders of different gas production rates. The deposited hydrates in the tubing under low testing rates will be decomposed under high rates to reduce the risk of hydrate plugging without hydrate inhibitor injection. A case study is carried out to investigate the applicability of this method. The results show that the maximum dimensionless thickness of hydrate deposit reaches 68.14% under the conventional testing order, but decreases to 33.59% by using the proposed method. It is indicated that the proposed method can obviously decrease the risk of hydrate plugging without using hydrate inhibitor injection. Hence, the proposed method is a more economical and environmentally friendly method for hydrate plugging prevention, which can be applied as an alternative to the present prevention methods during deep-water gas well testing.