The invention provides a three-dimensional interface inversion method fusing geological constraints and a
level set function, and relates to the technical field of
geophysical inversion and imaging, and the method comprises the steps: obtaining geological
prior information, carrying out the parametric modeling of an underground structure of a research region through a
Gaussian random field, and generating a
model parameter vector; and simulating the propagation process of seismic
waves in a
seismic wave speed model by using a forward modeling calculation method, carrying out iterative optimization on
model parameter vectors based on an EKI set Kalman inversion method, recovering an underground three-dimensional structure in a research area, and carrying out interpretation and
verification in combination with drilling data to obtain structural characteristics and
resource distribution of the research area. According to the method, unified parametric modeling is performed on speed disturbance and interface forms through a
Gaussian random field, and a
level set function is introduced to represent discontinuous layering, fault
cutting, inclusion embedding and other complex geological interfaces, so that collaborative inversion of a speed field and a structure boundary under the same optimization framework is realized; and geometric expressive power and geological consistency of the model are improved.