The Packard One-Twenty (also One Twenty and 120) was an automobile produced by the Packard Motor Car Company of Detroit, Michigan from 1935 to 1937 and from 1939 through the 1941 model years. The One-Twenty model designation was replaced by the Packard Eight model name during model years 1938 and 1942.

The One-Twenty is an important car in Packard's history because it signified the first time that Packard entered into the highly competitive mid-priced eight cylinder car market. Packard enthusiasts view the production of the One-Twenty and the Six/One-Ten models as the start of Packard losing its hold on the market as the premier American luxury automotive brand.

The introduction of the One-Twenty (and later the Six/One-Ten models) was a necessary move to keep Packard in business during the final years of the Great Depression. The reason the company decided to forgo the development of a companion brand name to sell the less expensive models may have been linked to its single production line capability at its Grand Avenue manufacturing plant as much as to the expense of launching a new brand of automobile. By making the One-Twenty a Packard, the car could be brought to market quickly, and would afford buyers the cachet of owning a Packard.

1935-1939

In its introduction year, the Packard One-Twenty was available in a broad array of body styles including two and four-door sedans, convertible and Club Coupe. The One-Twenty was powered by Packard's L-Head Eight cylinder engine producing 110 bhp (82 kW) at 3850 rpm. Prices for the car ranged from $980 for the three-passenger business coupe to $1,095 for the Touring Sedan. Introduced in January 1935, the car was an immediate success with consumers with Packard producing 24,995 One-Twentys compared to 7,000 of all other type Packards for the year.

For 1936 Packard increased the displacement on the L-Head Eight, increasing its output to 120 bhp (89 kW), making the car capable of clocking a top speed of 85 mph (137 km/h). The One-Twenty added a convertible four door-sedan model which was the most expensive model in the range priced at $1,395. A total 55,042 units rolled off the line in 1936, the highest production that the One-Twenty would reach.

In 1937, the One-Twenty went up-market as company introduced the Packard Six, the first six cylinder Packard in ten years. For 1937 the One-Twenty broadened its model range and was now available in "C" and "CD" trim levels. The line also added a wood-bodied station wagon, Touring Sedan and limousine built on a 138" (inch) wheelbase and priced under $2,000. Introduced in September 1936, 50,100 units were produced during series production.

For 1938, the One-Twenty name was dropped and its model folded into the Packard Eight model range, and bringing the model name into parity with the Packard Six.

Returning to the Packard model range, the One-Twenty continued to be offered in a full range of body styles from coupe to Touring Limousine, with prices for the model range between $1,099 and $1,856. New for the year was introduction of column shifting, which did away with the floor shifter. Introduced in September 1938, a total of 17,647 units were built during the recession year which saw all automotive production the 1937 model year.