Even though the economic benefit of Bt cotton adoption in the short-run has been well documented, the dynamics of this benefit remain unclear. In particular, the possibility of pest resistance build-up and secondary pest outbreaks has caused concern regarding the sustainability of this economic benefit in the long run. Hence, this study analyzes the economic impact of Bt cotton and its dynamics in China. Using nationally representative long panel data for 1997–2012, we show that this economic benefit continues 15 years after the commercialization of Bt cotton.