Antonio Rungi said he had never intended to put sisters on the catwalk, but had wanted to erase a stereotype of them as being old and dour.
He had wanted to hold the contest online on his internet blog.
Father Rungi said he changed his mind after the local religious authorities expressed their displeasure.
"My superiors were not happy. The local bishop was not happy, but they did not understand me either," Father Rungi told Reuters news agency from the town of Mondragone, near Naples.
"It was interpreted as more of a physical thing," he said. "Now, no one is saying that nuns can't be beautiful, but I was thinking about something more complete."
He said he had intended to showcase the good works that nuns do, especially in education and health care, so as to boost interest in religious vocations.
"We have to draw more attention to the world of nuns, who are often not sufficiently appreciated by society," he wrote in his blog.
"Nuns are - above all - women, and beauty is a gift from God," he told Italy's Corriere della Sera newspaper before he cancelled the project.
He had wanted nuns to send their photos to him, so that internet users could then choose the winner.
Father Rungi said the idea of the contest had been put to him by nuns themselves.
Priest (基督教)牧師;(天主教)神父, 神職人員;教士;僧人;祭司
bishop (天主教及英國國教等的)主教, (基督教的)監督