Abstract:Third party monitoring is an advanced management mode. It has been widely used in subway construction in China. Qingdao subway cross the strata with combination structure as soft in upper part and hard in lower part. It is different with other cities in third party monitoring in subway construction. Based on practices of third party monitoring in the construction of Qingdao Metro Line 1, purpose, task and process of third party monitoring have been introduced in this paper. Problems occurred in third party monitoring in the construction of Qingdao Metro works has been discussed, and some optimization thoughts and suggestions have been put forward as well.