The invention discloses an InSAR two-dimensional earth surface deformation monitoring method based on adjacent track data. The method comprises the following steps of firstly, using the SAR data of adjacent tracks to obtain the earth surface deformation measurement values of an earth surface at two different slant distance directions; then, acquiring two different slant distance direction deformation measurement values of the common area of adjacent tracks; calculating the incident angle and the azimuth of each point at first and second rails in the common area; and then, constructing the coefficient matrix for each point; and finally, according to the strict geometric relationship between the imaging geometry of a satellite and earth surface deformation, ignoring north-south deformation and establishing an equation set, and according to a least squares criterion, solving and acquiring earth surface two-dimensional deformation. In the invention, the technical bottleneck of InSAR two-dimensional deformation monitoring without a lifting track data area is broken through, an InSAR technology is actively promoted to develop towards a practical direction, and an important scientific value is possessed for studying a geophysical process and an inversion geological hazard parameter.