By using 14 categories of manufacturing data, a calculation has been made of the technical complexity of manufacturing export in 31 provinces, municipalities and autonomous regions of China from 2002 to 2021, followed by an investigation of the degree of manufacturing upgrading, as well as an inquiry into the convergence characteristics of manufacturing upgrading by applying δ convergence, absolute β convergence and conditional β convergence. It is found that the technical complexity of manufacturing export in each province has experienced a significant increase during the sample period with δ convergence characteristics in the whole country and four regions; there is no absolute β convergence in the eastern and northeastern regions but in the central and western regions nationwide. The phased analysis results show that from 2002 to 2004, only the western region of China and the four major regions are characterized with absolute β convergence; from 2005 to 2012, there was absolute β convergence in the whole country and other regions except the eastern region. From 2013 to 2021, the whole country and four major regions showed a significant trend of absolute β convergence with a significant characteristic of conditional β convergence. Based on this, some countermeasures and suggestions have been proposed for a coordination of the balanced development in the manufacturing industry region and implementation of the new strategy for provincial differentiated development.