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The migrating terdiurnal tide at the mesosphere and lower thermosphere(MLT)is suggested to contribute to the formation of the well-known Midnight Temperature/Density Maximum(MTM/MDM)in the upper thermosphere with a significant seasonal variation. In this study, the models TIEGCM and eCMAM are utilized to investigate the seasonal variations of the upward propagation of terdiurnal tide from the MLT. Three main conclusions are drawn from a series of controlled simulations:1)Both the background zonal and meridional winds in thermosphere can significantly affect the upward propagation of the terdiurnal tide.2)The terdiurnal tide in the MLT impacts not only on the latitudinal distribution and magnitude of the terdiurnal component in upper thermosphere but also on the influence of the background winds on the terdiurnal tidal upward propagation.3)The hemispheric asymmetry in zonal mean and vertical gradient of the background temperature contributes to the seasonal variation of the terdiurnal tidal upward propagation as well.