As end treatment of industrial pollution sources advances, their end emission space continuously shrinks. Industrial structural adjustment is an effective means in mitigating regional environmental pressure. This paper, based on status of three industrial structures in Sichuan, uses Theil index and industrial structure advancing index to estimate industrial structure rationalization extent and advancing level from perspectives of Sichuan province, five economic zones and cities, statistically analyzes the changing trend of leading industries, and applies component data model and ARIMA model to predict their percentages of three industries, aiming at offering references for Sichuan to make industrial structure optimization policies. It concludes that Sichuan's industrial structure has been consistently upgrading and improving, with large gaps within or among regions. Traditional energy, resources-intensive industries and primary processing industry of agricultural products still hold a major fraction, except Chengdu plain economic zone with developed electric information. This paper presents suggestions on enhancing co-integrated development within and among regions, boosting internal structural optimization of the secondary industry for Sichuan's industrial structural upgrading.