BBC News reports taht Dagoberto Valle Arriaga had confessed in 2005 to killing his son, Oscar.
State prosecutors have not released the boy's age nor any details about his murder, but local media are reporting that he was 16 when he was killed.
Mr Valle, who was a priest in the city of Texcoco, on the outskirts of the capital, was arrested ion 2006.
He was accused of kidnapping his son in September 2005 and bringing him to the central state of Guanajuato before murdering him.
The authorities released no details of how the boy was killed, but it appears that his father dumped his body in the outskirts of a city called Acambaro.
Officials said he was afraid the Church would find out about the boy's existence and remove him from the priesthood for breaking his vows of celibacy.
Priest jailed for murdering son (BBC News, 9/8/07)
Mexican Priest Sentenced To 55 Years For Killing Love Child (All Headline News, 9/8/07)
LINKS (not necessarily endorsed by Church Resources)
Roman Catholicism in Mexico (Wikipedia) <