La Fayette Kellogg (February 1, 1819 – June 4, 1878) was an American merchant, court clerk, and Wisconsin pioneer.

La Fayette Kellogg was born in Elizabethtown, New York, and received his education in that state.

He was originally interested in mercantile pursuits, but, in August of 1840, he was appointed clerk of the Wisconsin Territory's Supreme Court.

His older brother Orlando Kellogg was a member of the United States House of Representatives from New York.

After her death in 1863, he went on to marry Helen Rosamond Adams, a sister of another prominent Madisonian.