This paper is based on a curved continuous box girder with variable width. The bracket stress in the process during construction in mobile formwork system is monitored and analyzed. It has elaborated the contents which mobile formwork bracket monitored and methods in the construction of curved continuous box girder with variable width. The bracket stress was analyzed using the numerical analysis method. Accordingly, the theoretical value related to bracket stress is calculated by finite element software-Midas Civil 2010. The model of the combination of transverse and longitudinal shift is put forward, which ensures the security of mobile formwork during construction. A real-time monitoring system is established, and reasonable warning value is set. Furthermore, the data related to bracket stress is measured. Eventually, comparing the values of the field measurement with the one of theoretical calculation, we concluded that the bracket remained safe in the construction process. The analysis of the bracket will afford the experience for the similar bridge constructions and embody preferable practical value.