in 2013, mamun competed at the moscow grand prix and won the all-around gold medal. she also won three gold medals and one bronze in the apparatus finals. at the 2013 european championships, mamun and her teammates won team gold for russia. she won a gold medal and three silver medals in the apparatus finals. mamun competed at the 2013 summer universiade, where she won all-around gold and three gold medals in the apparatus finals. at the 2013 world championships, mamun won two gold medals and a bronze in the apparatus finals. she was ranked first in the world during the 2013 season.