In order to prevent damage to the sensor caused by the camera receiving light during the phased array transmission process of low-earth orbit optical satellites， this paper proposes a sun avoidance method for phased array transmission tasks. Firstly， the vector pointing from the satellite to the sun in the geocentric fixed coordinate system and the vector pointing from the satellite to the ground station for phased array transmission were calculated， and the unit normal vector of the plane containing the two vectors was also calculated. Secondly， the vector pointing from the satellite to the ground station for data transmission was rotated at the maximum off-axis angle of the phased array by using the unit normal vector as the rotation axis， and the resulting vector was the sun avoidance vector of the satellite in the geocentric fixed coordinate system. Then， the expected attitude of the satellite in the orbital coordinate system was calculated by using the sun avoidance vector， the position of the satellite in the geocentric fixed coordinate system， and the transformation matrix from the geocentric fixed coordinate system to the orbital coordinate system， and the phased array pointing angle was also calculated. Finally， mathematical simulations and on-orbit tests of the proposed method were applied for the Jilin1-GF02D satellite. The simulation results show that when the maximum beam angle of the phased array is 60°， the probability of the camera and the sun angle being less than 90° during transmission using the sun avoidance method is reduced from 44.1% using the traditional staring attitude transmission method to 2.1% in December. The on-orbit tests of the Jilin1-GF02D satellite show that， when using the sun avoidance method under approximately the same conditions， the angle between the camera and the sun during transmission is increased from 31.3°-152.1°using the traditional staring attitude to 96.3°-180°， which verifies the feasibility and effectiveness of the sunlight avoidance method.