The thermal mechanism errors of deployment distortion in phased array antenna of spaceborne Synthetic Aperture Radar (SAR) play an important role in the ambiguity performance analysis.A mathematic model for deployment distortion error is founded according to the characteristics of the phase array antenna on SAR satellite.Based on paired echo theory

the expression of antenna pattern function under deployment distortion errors is obtained.The statistic model of the SAR ambiguity performance analysis with antenna deployment distortion errors is proposed.The ambiguity performance analysis method for deployment distortion errors is presented.The computer simulation results are presented with a L-band space-borne SAR phase array antenna

by which the correctness of the conclusion is validated.