The invention discloses a whole process monitoring system and a method for capital construction supporting communication engineering, wherein the system comprises a server and a client terminal. The server is configured to receive the information of the capital construction supporting communication engineering. The capital construction supporting communication engineering includes the serial number, the name, the state, the progress and the planning information of the capital construction supporting communication engineering. Then, a tree storage structure is created so that the serial number, the name, and the planning information of the capital construction supporting communication engineering are stored to the root nodes; and the state and the progress information of the capital construction supporting communication engineering are stored in the sub-nodes; the state and progress updating information of the capital construction supporting communication engineering are received in real time, and corresponding state and the progress information in the sub-nodes is modified; the planning information in the root nodes is compared in real time with the updated state and progress information of the capital construction supporting communication engineering; the mismatched information between the current state of the capital construction supporting communication engineering and the progress information and the planning information is outputted; and the client terminal is configured to receive the outputted information of the server and to display the information in real time.