Terrestrial digital video broadcasting system is mainly used to provide audio and video communication services, and can be applied to information dissemination in emergency situations. However, in some special circumstances such as war or natural disasters, the established signal transmitting system tends to be damaged and it may be difficult to achieve reliable broadcasting. In view of the above problems, this paper takes DVB-T system as an example and proposes a high reliable emergency warning method based on digital broadcast signaling aggregation, which can achieve high reliable short message transmission under low transmission power. In a pre-set fixed transmission mode, the method utilizes the saved signaling part to carry the short message data, uses the non-binary Low Density Parity Check Codes (LDPC) with the rate of 1/2 in the field of GF(16) and the repeat coding as the channel coding scheme, and uses Binary Phase Shift Keying as the modulation method. Further, the proposed method is tested and verified on the software-defined radio platform in an open environment. The results show that this method can achieve high reliable transmission of emergency short message data, and can be extended to other digital broadcasting system.