Dan Shechtman (Hebrew: דן שכטמן; born January 24, 1941) is the Philip Tobias Professor of Materials Science at the Technion – Israel Institute of Technology, an Associate of the US Department of Energy's Ames National Laboratory, and Professor of Materials Science at Iowa State University. On April 8, 1982, while on sabbatical at the U.S. National Bureau of Standards in Washington, D.C., Shechtman discovered the icosahedral phase, which opened the new field of quasiperiodic crystals, also referred to as "quasicrystals." For this discovery, he was awarded the 2011 Nobel Prize in Chemistry, making him one of six Israelis who have won the Nobel Prize in Chemistry.

Dan Shechtman was born in 1941 in Tel Aviv, in what was then Mandatory Palestine; the city became part of the new state of Israel in 1948. He grew up in Petah Tikva and Ramat Gan in a Jewish family. His grandparents had immigrated to Palestine during the Second Aliyah (1904–1914) and founded a printing house. As a child, Shechtman was fascinated by Jules Verne's The Mysterious Island (1874), which he read many times. His childhood dream was to become an engineer like the main protagonist, Cyrus Smith.

I thought that was the best thing a person could do. The engineer in the book knows mechanics and physics, and he creates a whole way of life on the island out of nothing. I wanted to be like that.

— Dan Shechtman

Shechtman is married to Prof. Tzipora Shechtman, Head of the Department of Counseling and Human Development at Haifa University, and author of two books on psychotherapy. They have a son Yoav Shechtman (a postdoctoral researcher in the lab of W. E. Moerner) and three daughters: Tamar Finkelstein (an organizational psychologist at the Israeli police leadership center), Ella Shechtman-Cory (a PhD in clinical psychology), and Ruth Dougoud-Nevo (also a PhD in clinical psychology).

After receiving his Ph.D. in Materials Engineering from the Technion in 1972, where he also obtained his B.Sc. in Mechanical Engineering in 1966 and M.Sc. in Materials Engineering in 1968, Shechtman was an NRC fellow at the Aerospace Research Laboratories at Wright Patterson AFB, Ohio, where he studied for three years the microstructure and physical metallurgy of titanium aluminides. In 1975, he joined the department of materials engineering at Technion. In 1981–1983 he was on sabbatical at Johns Hopkins University, where he studied rapidly solidified aluminum transition metal alloys, in a joint program with NBS. During this study he discovered the icosahedral phase which opened the new field of quasiperiodic crystals.

In 1992–1994 he was on sabbatical at National Institute of Standards and Technology (NIST), where he studied the effect of the defect structure of CVD diamond on its growth and properties. Shechtman's Technion research is conducted in the Louis Edelstein Center, and in the Wolfson Centre which is headed by him. He served on several Technion Senate Committees and headed one of them.

Shechtman joined the Iowa State faculty in 2004. He currently spends about five months a year in Ames on a part-time appointment.