Anthony Levandowski, the engineer charged in August with 33 counts of trade-secret theft from Google’s self-driving car project, reached a deal with U.S. prosecutors in which he will plead guilty to one count and the remaining charges will be dropped.

According to a court filing Thursday, Mr. Levandowski will plead guilty to the last count in the indictment, charging him with theft and attempted theft of trade secrets related to “Project Chauffeur,” as Google’s autonomous vehicle program was called at the time. Specifically,...