A process is provided for producing petroleum coke that is high in strength and sufficiently small in thermal expansion coefficient and sufficiently suppressed from puffing. The process includes coking a feedstock containing a first heavy oil having a sulfur content of 1.0 percent by mass or less, a nitrogen content of 0.5 percent by mass or less, and an aromatic index of 0.1 or greater, produced by hydrodesulfurizing a heavy oil with a sulfur content of 1 percent by mass or more under conditions (1) where the total pressure is 10 MPa or greater and less than 16 MPa and the hydrogen partial pressure is 5 MPa or greater and 16 MPa or less or conditions (2) where the total pressure is 20 MPa or greater and 25 MPa or less and the hydrogen partial pressure is greater than 20 MPa and 25 MPa or less, and a second heavy oil with an aromatic index of 0.3 or greater and an initial boiling point of 150° C. or higher.