NGC 4157 is a spiral galaxy in the constellation Ursa Major.

The galaxy lies about 55 million light years away from Earth, which means, given its apparent dimensions, that NGC 4157 is approximately 125,000 light years across.

[6] The hydrogen disk of NGC 4157 is symmetric and slightly wrapped, indicating no strong interaction with other galaxies, and extends to twice the size of the optical disk.

There is also radio emission extending southwards from the north-eastern end of the disk.

[6] The group is part of the Ursa Major Cluster, a large association of mostly spiral galaxies lying north of the Virgo Cluster, that is part of the Local Supercluster.