Lengby (pronounced lang - bee) is a city in Polk County, Minnesota, United States.

It is part of the Grand Forks ND-MN Metropolitan Statistical Area.

[7] In 1980, Jean Hilliard survived being frozen for six hours in subzero temperatures;[8] her story was later featured on Unsolved Mysteries.

According to the United States Census Bureau, the city has a total area of 0.246 square miles (0.64 km2), all land.

The racial makeup of the city was 95.3% White, 2.3% Native American, and 2.3% from other races.

There were 7.7% of families and 9.1% of the population living below the poverty line, including no under eighteens and 31.6% of those over 64.