NGC 3645 (also NGC 3630, UGC 6349, MCG 1-29-31 and PGC 34698) is a magnitude +12.1 barred spiral galaxy located 68 million light-years away in the constellation Leo.
The galaxy was discovered by German-British astronomer William Herschel using a 47.5 cm (18.7 inch) f/13 speculum reflector at Datchet, Berkshire, on the 23rd February 1784. The galaxy was rediscovered by John Herschel in April 1828 and relisted as NGC 3630.
Right Ascension 11h 20m 17.0s, Declination Dec +02° 57' 52"