Robert Tappan Morris (born November 8, 1965) is an American computer scientist and entrepreneur. He is best known for creating the Morris worm in 1988, considered the first computer worm on the Internet.

Morris was prosecuted for releasing the worm, and became the first person convicted under the then-new Computer Fraud and Abuse Act (CFAA). He went on to cofound the online store Viaweb, one of the first web applications, and later the venture capital funding firm Y Combinator, both with Paul Graham.

He later joined the faculty in the department of Electrical Engineering and Computer Science at the Massachusetts Institute of Technology (MIT), where he received tenure in 2006. He was elected to the National Academy of Engineering in 2019.