In the research, the distribution of snow cover on the sea ice surface in the Arctic summer is analyzed using the observations during the 3rd Chinese Arctic Expedition. It is found that there are six firn statuses within the snow cover from surface to bottom along the Arctic cruise. They are new snow, wind crust, ice slice, depth hoar, frozen coarse snow and infiltration-congelation ice. Snow surface is often covered by new snow or wind crust, 2～3 cm in depth. Mean snow density is (304.01±29.00)kg·m^-3, and surface snow density is always smaller than the subsurface snow density, owing to snow densification. Snow depth, snow water equivalent and new snow amount decrease gradually from south to north, indicating the climate over snow cover is mainly controlled by precipitation. Therefore, melting and evaporation are not the principal factors that should be taken into account in the assessment of snow cover at the end of the Arctic summer. There is a distinct vertical gradient in snow temperature profile; the mean temperature at snow surface is -2.01～0.96 ℃, much higher than the temperature in the interface between snow and sea ice.

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