Cayetano Arellano y Lonzón (March 2, 1847 – December 23, 1920) was the first Chief Justice of the Supreme Court of the Philippines under the American Civil Government.
Cayetano Arellano had occupied a high position in Aguinaldo's government.
He worked with the Americans under General Otis and re-establish the Audiencia Territorial, and renamed it the Supreme Court.
He was Chief Justice from 1901 until his retirement on April 12, 1920, making him the longest serving Chief Justice.