New Bloomfield is a city in Cedar Township, Callaway County, Missouri, United States. The population was 669 at the 2010 census. It is portion of the Jefferson City Metropolitan Statistical Area.

In 1827, a ‘Round Prairie Post Office’ was opened northwest of New Bloomfield, near what became Guthrie in the region of 50 years later, and near the southern be bordering to of a much larger historic Round Prairie Township (subdivided on 1890 to create what later became the northern ration of Guthrie Township).

In 1836, a historic town of ‘Bloomfield’, next to or containing the Round Prairie Post Office, was first surveyed.

In 1841, the Round Prairie Post Office was shut by the side of and moved not quite 1/2 mile southward, clearly into Cedar Township, and was renamed ‘New Bloomfield Post Office’, around which today’s town of New Bloomfield formed. The credited establishment of the town of Guthrie as ‘Bigbee’ and a extra Guthrie Post Office (closed in 1954) followed in 1872 and 1874. The Chicago & Alton Railroad went from the Missouri riverport at Cedar City, through Holts Summit, then New Bloomfield and Guthrie, then veered northeast toward Carrington, then Fulton, then McCredie, Auxvasse, and into Audrain County and the city of Mexico, and thereafter toward Illinois and Chicago to the east, or to Kansas City to the west. Connection to St Louis was made via locations across the Mississippi River in Illinois until the MKT railroad was built in the 1890s. A ferry boat connected the Cedar City railway station to Jefferson City until a bridge was built in 1896. The New Bloomfield railroad station was located in what is now the New Bloomfield City Park. Details of relevant township boundary changes are resolution in the articles on both Round Prairie Township and Cedar Township.