Lanier was probably born in Greenwich and first taught by his father, who played the sackbut. In 1613 he composed a masque for the marriage of the Earl of Somerset jointly with Giovanni Coperario and others. He also wrote music and made sets for Ben Jonson's Masque of Augurs and Lovers Made Men.
In the 1610s, Lanier was appointed as a lutenist to the King's band. He also sang and played the viol.
From 1625 he made a series of visits to Italy to collect paintings for the King, during which he heard the new Italian music being written by the likes of Claudio Monteverdi. This led to him being one of the first English composers to introduce monody and recitative to England.
In 1626, Lanier became the first to hold the title Master of the King's Musick. During the Commonwealth of England he lived in the Netherlands, but returned to resume his duties in 1660.
There is only one painting which can be identified as being by Lanier, a self portrait in the music faculty of Oxford University.