Joseph M. Hellerstein (born June 7, 1968) is an American computer scientist and professor specializing in data-centric systems, database management, distributed computing, and related fields. He holds the position of Jim Gray Professor of the Graduate School in the Electrical Engineering and Computer Sciences (EECS) department at the University of California, Berkeley, where he has taught thousands of students and advised over 30 Ph.D. candidates. Hellerstein's research has earned him prestigious accolades, including the ACM SIGMOD Edgar F. Codd Innovations Award (2023), multiple ACM SIGMOD and VLDB Test of Time Awards, ACM Fellowship (2009), Alfred P. Sloan Research Fellowship, and inclusions in MIT Technology Review's TR10 and TR100 lists, as well as Fortune's 50 Smartest People in Tech. His influential ideas have been integrated into commercial and open-source software from companies like IBM, Oracle, and PostgreSQL.

Hellerstein has bridged academia and industry through entrepreneurial ventures and leadership roles. He co-founded Trifacta in 2012 (acquired by Alteryx in 2022), serving as founding CEO and Chief Strategy Officer, stemming from the Wrangler research project. He also co-founded RunLLM in 2020, focusing on AI assistants. Currently, he is Vice President and Distinguished Scientist at Amazon Web Services (AWS). Past roles include Director of Intel Research Berkeley (2003-2005) and Engineering Manager at Greenplum (acquired by EMC in 2010). He serves on technical advisory boards for various computing and internet companies.

Hellerstein earned his AB in Computer Science from Harvard University (1986-1990), MS from UC Berkeley (1991-1992), and PhD from the University of Wisconsin-Madison (1995), with a thesis on query optimization. He is the brother-in-law of Rabbi Efrem Goldberg.