[Objectives]  To investigate the development of resistance to chlorfluazuron in the diamondback moth (DBM), Plutella xylostella (L.), in fields with different cropping patterns, and thereby provide information useful for managing the development of resistance to this insecticide. [Methods]  Data were obtained during the agricultural industry standard of the People’s Republic of China’s “Crucideline monitoring program for insecticide resistance in P. ylostella on cruciferous vegetables” (NY/T 2360-2013). [Results]  Compared to a DBM sensitive strain, resistant strains from four monitoring stations  differed in their resistance to chlorfluazuron due to differences in geographical locations, vegetable cropping patterns, and methods of insecticide use. On the whole, the resistant strain from Guangzhou, Guangdong, where there was a small-scale, year by year, planting model, was the most resistant, with moderate, or high-moderate resistance to chlorfluazuron being the norm (maximum RR value = 437.58). The next most resistant strain was that from Huizhou, Guangdong, where there was a scale-successive cropping pattern, in which moderate, or high-moderate, resistance to chlorfluazuron was typical (maximum RR value = 337.18). Resistance of the Lianzhou, Guangxi strain was similar to that of the Guangzhou and Huizhou strains, but was slightly less than that of these strains. This strain had the lowest resistance to chlorfluazuron (maximum RR value = 23.24), due to the small scale of the planting model in the mountainous region inhabited by this strain. Resistance data from the four monitoring stations showed a similar trend. In 2008, resistance at most monitoring stations was moderate, or high-moderate, then decreased in 2009-2011 after the use of chlorfluazuron was discontinued. However, in 2012, chlorfluazuron was once again used to control DBM at the four monitoring stations with the not unexpected result that resistance once again increased. [Conclusion]  The resistance of DBM to chlorfluazuron is unstable and positively correlated with frequency of use and dosage. Discontinuation of use, or over use of this pesticide, can cause resistance to decrease or increase, respectively, within a short period.