Lambrocus Thomas (1610? - 1672)} was a Welsh clergyman who served as Canon Chancellor and Dean of Chichester Cathedral.
Thomas studied at the University of Franeker where he matriculated on 2 June 1641 and graduated, in divinity, on 4 October 1643. He was incorporated, on his doctors degree, at Cambridge University, in 1670.
Lambrocus Thomas was married to Margaret Thomas alias Briggs. His wife outlived him and she was the executrix of his will.
At the end of the 17th century the full number of Canons Residentiary, at Chichester Cathedral, was four. In 1661 when one of the Canons Residentiary (Nicholas Garbrand) resigned, he was not replaced. In 1663 Thomas, who by that time was chancellor, made the number of residentiaries back up to four. When he eventually became Dean in 1671, he continued to hold the residentiary post. He was the last person, at Chichester, to hold the post of Canon Residentiary and Dean simultaneously.
Lambrocus Thomas died 27 November 1672. Thomas Abingdon writing in 1717 recorded that a memorial plaque in black marble had been attached to the north wall at the upper end of the Chichester Cathedral chancel. The original text was in Latin, an English translation follows: