The Lancia Ro, Lancia Ro-Ro and Lancia 3Ro were 4x2 heavy trucks built by Italian manufacturer Lancia from the 1930s through the 1940s for military and civilian use. The 2-cylinder diesel Ro was produced from 1933 to 1939, the 3-cylinder diesel Ro-Ro from 1935 to 1939 and the improved 5-cylinder diesel 3Ro from 1938 to 1947.

Ro and 3Ro saw extensive military service during the Second Italo-Ethiopian War and World War II, chiefly as two of the main heavy trucks of the Royal Italian Army.

The Lancia Ro (or 264) was the first of a family of Lancia 4x2 heavy trucks, starting in 1933. The Ro was built with two versions, a three-cylinder gasoline (BM) engine or a two-cylinder diesel (Nm) engine. The Ro was particularly robust truck, considered reliable, requiring little maintenance, and easy to drive.^{[citation needed]} It was the first Italian truck to receive a 4 speed transmission.

The Ro NM (for Nafta Militare or "diesel, military") military truck was produced in 3,056 units from 1934 to 1938, and eventually replaced by the improved 3Ro.

Built by Lancia under license from German firm Junkers, the Tipo 89 engine fitted to the Ro was a compact 3,180 cc (194 cu in), four opposed-piston, straight-two cylinder, two-stroke diesel. It developed 64 hp (48 kW) at 1,500 rpm. The transmission used a Tipo 126 4-speed manual transmission with a 2 speed auxiliary, for a total of 8 forward and 2 reverse speeds.

From 1933 to 1939 429 civilian Ro trucks were built. This version differed mechanically from the military type mainly for its wider tracks front and rear, as well for the availability of a longer 4,250 mm (167.3 in) wheelbase alongside the normal version.

From 1934 to 1938 Lancia built 1701 military type Ros fitted with a petrol engine, intended for colonial duty—the Ro BM (364), for Benzina Militare or "petrol, military".

Its Tipo 98 petrol engine was a side valve 5,120 cc (312 cu in) inline-four, developing 65 hp (48 kW) at 1,700 rpm.