The marijuana was discovered by U.S. Customs and Border Protection agents Nov. 13 when they inspected a truck purportedly carrying a load of fresh squash, the Nogales (Ariz.) International reported Tuesday.
The drugs, seized at the Nogales-Mariposa port of entry, were valued at more than $10 million.
Christopher Maston, CBP's executive director of operations, called the seizure "an indication of the desperation on the part of transnational criminal organizations to move their product across the border."
The driver, Pedro Corona-Moreno of Hermosillo, Mexico, was arrested, Maston said.
The seizure broke the record in Arizona of 14,000 pounds of marijuana seized by CBP in January.