According to the Tianfeng Securities Research report, the PMI index of the construction industry in September was 56.2%, an increase of 2.4pct from the previous month, and the prosperity of the construction industry continued to improve. It is suggested that we should pay attention to the investment targets of the three main lines: 1) low valuation: under the valuation system with Chinese characteristics, it is good for the blue chip construction of central enterprises, China Construction, China Rallway, China Railway Construction Corporation, etc., highly flexible local state-owned enterprises Sichuan Road and Bridge, Shandong Road and Bridge, Shanghai Construction Engineering, in addition, attach importance to the slab opportunities brought by "Belt and Road Initiative" to international projects. 2) Architecture +: China Electric Power Construction, China Energy Construction, Sowen Electric Power, Jianghe Group, etc., related to new energy; Chinese chemistry, 3D chemistry, Donghua science and technology related to chemical industry, etc. 3) Professional engineering: steel structure (Honglu Steel structure, Lippert) is recommended, and other food security related to people's livelihood (COFCO Science and Technology). It is recommended to pay attention to subdivision races such as heating energy saving (Renner Intelligence), semiconductor clean room (Ya Xiang Integration, Shenghui Integration) and so on.