The invention belongs to the field of construction safety monitoring and wireless communication and discloses a construction tunnel safety protection method based on a wireless sensor network and a monitoring system thereof. The method is as follows: by acquiring environment, work amount and locating data of personnel in a tunnel, realizing alarming services of six types of dangerous situations and corresponding safety protection means, calling a protection plan to take protection measures on key parts of the system when emergent (dangerous) events occur, and with the purpose of guaranteeing personal safety, releasing a control command. The system comprises a wireless sensor network based on industrial wireless communication standard WIA-PA, a positioning network and a mobile network. If the dangerous situation develops further, the system exchanges data with a remote mobile server by a 3G network, leads a community security system into the range of a construction tunnel safety protection system, and provides united rescue of communities and disaster control services. The invention is used for tunnel construction safety monitoring, and a computer or 3G mobile equipment can obtain construction site information at any time; and the installation of the WIA-PA wireless network is flexible, and the formed safety protection system and sensing early-warning network make contribution to solving the problem of tunnel safety construction fundamentally.