Robert Lewers (March 15, 1836 – November 3, 1926) was a businessman during the Kingdom of Hawaii, Republic of Hawaii, and Territory of Hawaii. Born in New York City, he accompanied his cousin Christopher H. Lewers to Honolulu. The two of them worked to build a lumber firm, and benefited from the influx of sugar plantation customers following the Reciprocity Treaty of 1875. Upon the death of Christopher, Robert continued the business and in 1880, he and partner Charles Montague Cooke renamed it Lewers & Cooke, Ltd.