Osbert Parsley (1510/1511 – 1585) was an English Renaissance composer and chorister. Few details of his life are known, but he evidently married in 1558 and lived for a period in the parish of St Saviour's Church, Norwich. A boy chorister at Norwich Cathedral, Parsley worked there throughout his musical career. He was first mentioned as a lay clerk, was appointed a "singing man" in c.1534, and was probably the cathedral's unofficial organist for half a century. His career spanned the reigns of Henry VIII and all three of his children. After the Reformation of 1534, the lives of English church musicians changed according to the official policy of each monarch.