Turner syndrome (TS) was first described as a genetic disorder in 1938, and was found to result from the X chromosome being partially or completely absent. Turner Syndrome with 45, X karyotype was observed in 1–2 percent of human conceptions, 10 percent of pregnancy losses in the first trimester, and 1 percent of pregnancy losses are still births. More than 99 per cent of 45,X fetuses end up with abortion, typically through the 28th week of gestation, suggesting that living 45,X individuals must have mosaicism for another cell line (5,6) We report a case of an 18–year–old Delhi resident presented with history of Amenorrhoea in the Department of General Medicine at SGT University Gurugram, poorly developed secondary sexual characters and increased forgetfulness. Her karyotyping revealed Mosaic variant 45, X[10]/46, X, i(X)(q10)[10], which is a very rare variant and therefore we are reporting this case.