约翰·亚历山大·怀特John White Alexander（1856年10月7日——1915年5月31日），美国画家。亚历山大出生在阿勒格尼，宾夕法尼亚州，现在的一部分宾夕法尼亚州匹兹堡。在婴幼儿时期父母双亡，他由他的祖父母抚养，并在12岁的时候，成为了电报男孩在匹兹堡。
1881年，他回到纽约，并迅速取得了肖像画了巨大的成功，他的保姆间编号奥利弗·温德尔·霍姆斯，约翰·巴勒斯，亨利G.马昆德，RAL史蒂文森和总裁McCosh普林斯顿大学。他在第一个展览巴黎沙龙 1893年获得了巨大成功，并随后立即将他当选为法国兴业国立美术学院。许多额外的荣誉授予了他。1889年，他画了耶利米米尔班克太太的广受欢迎的肖像惠特曼和她的丈夫，一个耶利米米尔班克。1901年他被任命为骑士的荣誉军团，并在1902年他成为了成员国家设计学院，在那里他担任总裁，从1909- 1915。他是成员美国艺术暨文学学会和总统壁画画家的国家协会。在他收到的金牌是那些的巴黎世界博览会（1900年）和世界博览会在圣路易斯（1904年）。
John White Alexander (7 October 1856 – 31 May 1915) was an American portrait, figure, and decorative painter and illustrator.
Alexander was born in Allegheny, Pennsylvania, now a part ofPittsburgh, Pennsylvania. Orphaned in infancy, he was reared by his grandparents and, at the age of 12, became a telegraph boy in Pittsburgh. Edward J. Allen became an early supporter and patron of John W. Alexander, adopting the orphaned Alexander while he worked at the Pacific and Atlantic Telegraph Co. as a young man. Allen brought Alexander to the Allen home at "Edgehill" where Alexander painted various members of the Allen family, including Colonel Allen.His talent at drawing attracted the attention of one of his employers, who assisted him to develop them. He moved to New York City at the age of eighteen and worked in an office at Harper's Weekly, where he was an illustrator and political cartoonist at the same time that Abbey,Pennell, Pyle, and other celebrated illustrators labored there. After an apprenticeship of three years, he travelled to Munich for his first formal training. Owing to the lack of funds, he removed to the village of Polling, Bavaria, and worked with Frank Duveneck. They travelled to Venice, where he profited by the advice of Whistler, and then he continued his studies in Florence, the Netherlands, and Paris.
In 1881 he returned to New York and speedily achieved great success in portraiture, numbering among his sitters Oliver Wendell Holmes, John Burroughs, Henry G. Marquand, R. A. L. Stevenson, and president McCoshof Princeton University. His first exhibition in the Paris Salon of 1893 was a brilliant success and was followed by his immediate election to the Société Nationale des Beaux Arts. Many additional honors were bestowed on him. In 1889 he painted for Mrs. Jeremiah Milbank a well-received portrait of Walt Whitman and one of her husband, Jeremiah Milbank. In 1901 he was named Chevalier of the Legion of Honor, and in 1902 he became a member of the National Academy of Design, where he served as President from 1909-1915. He was a member of the American Academy of Arts and Letters, and President of the National Society of Mural Painters. Among the gold medals received by him were those of the Paris Exposition (1900) and the World's Fair at St. Louis (1904).
He served as President of the National Society of Mural Painters from 1914 to 1915.
Alexander was married to Elizabeth Alexander Alexander, to whom he was introduced in part because of their shared last name. Elizabeth was the daughter of James Waddell Alexander, President of the Equitable Life Assurance Society at the time of the Hyde Ball scandal. The Alexanders had one child, the mathematicianJames Waddell Alexander II.
John White Alexander died in New York on 31 May 1915.