High-precision height acquisition needs to correct the interferometric parameters errors by interferometric calibration for Interferometric Synthetic Aperture Radar (InSAR) system with many Ground Control Points (GCPs). For the situation that some areas probably only have little GCPs or even no GCPs, a new high-precision calibration method for airborne InSAR based on bundle adjustment is needed, in which the Control Points (CP) selection method is a major point which has a crucial influence on the precision of InSAR calibration. A model-based CP selection method for calibration of airborne InSAR with sparse GCPs is proposed in this paper, which adopts the polynomial model fit method to choose CP based on the sensitivity characteristic of inSAR interferometric parameters. A joint calibration is made with the real InSAR data and the results confirm the
validity and rationality of the proposed method.