The priest, identified as Father Sean John, was abducted by gunmen a week ago in the violence-plagued southern state of Guerrero, Bishop Alejo Zavala Castro said.
The priest had been working in Mexico for the past three years, he said.
He was kidnapped while driving a pickup truck after celebrating mass in an indigenous village, the bishop said.
There has been no word from him nor any ransom demand, he added.
Guerrero is one of Mexico’s poorest states and a hotbed of drug trafficking activity. Kidnappings and killings by organized crime gangs are common there.