Referring to the strong Italian influence on the English madrigal, The New Grove Dictionary of Music and Musicians states that Morley was "chiefly responsible for grafting the Italian shoot on to the native stock and initiating the curiously brief but brilliant flowering of the madrigal that constitutes one of the most colourful episodes in the history of English music.

While Morley attempted to imitate the spirit of Byrd in some of his early sacred works, it was in the form of the madrigal that he made his principal contribution to music history.

His work in the genre has remained in the repertory to the present day, and shows a wider variety of emotional colour, form and technique than anything by other composers of the period.

Usually his madrigals are light, quick-moving and easily singable, like his well-known "Now Is the Month of Maying" (which is actually a ballett); he took the aspects of Italian style that suited his personality and anglicised them.

Morley's Plaine and Easie Introduction to Practicall Musicke (published 1597) remained popular for almost two hundred years after its author's death, and is still an important reference for information about sixteenth century composition and performance.

Thomas Morley was buried in the graveyard of the church of St Botolph Billingsgate, which was destroyed in the Great Fire of London of 1666, and not rebuilt.