Agnia Sergeyevna Losina-Losinskaja (Агния Сергеевна Лозина-Лозинская) (1903–1958) was a Russian botanist. Her family name is also transcribed as Lozina-Lozinscaia, and Lozina-Lozinskaja. She is the author or co-author of the botanical names of at least 216 taxa, including species of Calligonum, Cortusa, Fragaria, Micranthes and Rheum, as well as Galanthus woronowii and the synonym Muscarimia muscari. Two economically important crop plants were amongst her interests. She produced a monograph on Rheum (rhubarb), suggesting that the genus had two primary centres of origin: the older being in China, the younger in Iran, spreading later into Central Asia. She also wrote a review of the genus Fragaria (strawberries). She contributed to a number of volumes of the Flora of the USSR, such as Volume