Martian upper atmosphere warming reflects the energy-materials interactions from the lower atmosphere layers. In this paper, we show a new phenomenon that enhances Mars upper atmosphere density in the equatorial region during the winter periods. First, both accelerometer-derived density and NGIMS-measured species from MAVEN show that the winter equatorial region has a secondary warming peak compared with that of the high-latitude polar warming area. Second, the major neutrals (CO2, Ar, CO, N2, and O) indicate that the phenomenon extends at least up to 240 km during both day and night sides. Furthermore, the topographic-related longitudinal structure emerged in the equatorial sector indicates that the variations are more dynamical than we expected. The warming found in this study suggest to be dust-related and influenced by the evolution of the seasonal solar insolation. Both local factors, upward small-scale gravity waves and CO2 IR-thermal effect transfer, may play key roles in shaping the warming structure.