Abstract: Ultra-low orbit aircrafts have broad application prospects in ocean circulation monitoring and high-precision ground environmental investigations. The aerodynamic drag is a key factor affecting their service performance. An aerodynamic drag prediction model for ultra-low orbit aircrafts considering lateral drag effects is proposed, which is based on rarefied gas dynamics and DSMC method. Firstly, an aerodynamic model of the aircraft is established. The DSMC method is used to analyze the frontal and lateral aerodynamic drag of typical aircrafts with different forward and lateral areas, attack angles and, wall temperature ratios. Further, an aerodynamic drag prediction model considering lateral drag effects is proposed. Finally, the prediction model is validated by a complex satellite model. The research results indicate that the effect of lateral drag can reach the same order as the forward windward aerodynamic drag. The aerodynamic drag prediction model proposed considering lateral drag effects has high accuracy, with a deviation of less than 5% from the DSMC simulation result.