Abstract: The dynamic behaviors of particles are mainly affected by forces exerted on the particles in fluid. The particles suspended in gas are typically nonspherical. Forces on nonspherical particles depend on shape, orientation and momentum accommodation coefficients. The aspect ratio of ellipsoids and the incident angle of gas flow (the angle between the polar axis of an ellipsoid and the direction of gas flow) are the key factors, which lead to the transport dynamics of nonspherical particles different from spherical particles. In this study, we analyzed the forces on ellipsoids and calculated the drag and lift coefficients using the direct simulation Monte Carlo (DSMC) method. The results obtained by the DSMC method are in agreement with theoretical predictions. Across various Knudsen numbers, the variations of drag and lift coefficients are analogous. It is found that the theoretical formulae in the continuum regime can be extended to the transition and free molecular regimes. There is a maximum of drag coefficient where the incident angle is 90° for prolate ellipsoids. However, the drag coefficient is a minimum in the condition of 90° for oblate ellipsoids. Lift coefficients of prolate and oblate ellipsoids increase to a maximum at 45° and subsequently decrease. At the same incident angles, drag and lift coefficients decrease with speed ratios in the free molecular regime. For a particle suspended in the free molecular regime, the drag and lift coefficients are proportional to the momentum accommodation coefficients of ellipsoids.