'Ton-grain field' (dūn liáng tián) is a technical agricultural term referring to farmland that yields at least one metric ton (1,000 kg) of grain per mu — a traditional Chinese unit of area equal to about 667 square meters (roughly 0.165 acre). Though sometimes loosely translated as 'per acre', the standard metric benchmark is per mu in official Chinese agricultural policy and reporting.

The term combines three characters: 吨 (dūn, 'ton'), 粮 (liáng, 'grain' or 'food crop'), and 田 (tián, 'field' or 'cultivated land'). It emerged in mid-20th-century China during efforts to boost food security and remains widely used in rural development reports, agricultural statistics, and extension services to measure high-yield farming success — especially for rice, wheat, and corn.