Tustin is a surname derived from the Old Norse name Þórsteinn like Dustin, through a Latinized form Tustinus, itself a variant of Turstinus, which Latinizes the Old Norman name To[r]stein, Tu[r]stin (now surnames Tostain, Toustain, Toutain). This Old Norse name, like Thorsten, is composed of the elements Thor (Þorr) and stein (steinn) "stone" together.
Notable people with the surname include:
Arnold Tustin (1899–1994), British engineer
Frances Tustin (1913–1994), British psychotherapist
George Tustin (1889–1968), Canadian politician
Norman Tustin (19–1998), Canadian Ice Hockey player
Septimus Tustin (1796–1871), American clergyman and Chaplain to the House of Representatives