The invention relates to a combined advanced prediction method based on priori form information constraint for a tunnel and other underground constructions. The method mainly comprises the steps that geological data and drilling data collected in a detection area are analyzed, advanced prediction data collection is conducted on an important high-risk water sudden-flooding area through a land sonar method, a transient electromagnetic method, a geological radar method and an induced polarization method, and determinacy detection result abnormality is used as known priori information; according to an obtain abnormal area, the direction vector and weight of the area are built, a priori information constraint diagonal matrix is formed through assembly, the induced polarization inversion is constrained, and the combined advanced prediction method based on priori form information constraint is achieved. The combined advanced prediction method achieves combined prediction data constraint, significantly suppresses multiplicity, and improves accuracy and reliability of combined advanced prediction. Three-dimensional space form prediction of a water-sudden-flooding disaster source in front of tunnel face, and recognition to the boundary of the water-sudden-flooding disaster source can be achieved particularly.