Antoine Videau, 64, was jailed for two years and given a further year's suspended sentence for defrauding the church and the faithful over 20 years. He was also fined 100,000 euros and deprived of his civic rights for three years.
Videau salted away the cash while he was in charge of the finances of the diocese, which comes under the Corsican bishopric.
The diocesan accountant, Bruno Servas, 56, was given a year's suspended sentence and fined 30,000 euros for fraud, which enabled him to pocket 100,000 euros.
Another diocesan employee, Marie-Thérèse Zavani, 64, was given a six-month suspended sentence for stealing 12,000 euros, part of which she placed in her mother's bank account. She was ordered to repay the stolen cash.