Manziel has expressed interest in joining the Cowboys but Jones strongly stated that he will not be signed.
"There's no chance," Jones told CBS Sports Radio. "Obviously Johnny needs to get his hands around his life. He needs to do the things that make him a good person off the field, I think, before he can ever be successful in our league."
Manziel experienced a disastrous two NFL seasons with the Cleveland Browns prior to being released last March. He had multiple off-the-field incidents that hindered his opportunities to play.
Even if Manziel were to be signed by a team, he would have to serve the four-game suspension he received in June for violating the NFL's substance-abuse policy.
Speculation about Manziel and the Cowboys continue to swirl due to the fact that the former Heisman Trophy winner played at Texas A&M. Also, Cowboys owner Jerry Jones has stated that he wanted to take Manziel in the first round of the 2014 NFL draft.
Regardless, it appears the current season will begin without Manziel being part of the NFL.
"Unfortunately, he has some things that are holding him back not only as a football player, but as a person in life," Stephen Jones said. "We certainly hope he gets his hands around that because he's obviously a guy who has some very unique successes in his life.
"I hope he is able to get his hands around his life, and at some point if he does, I'm sure he'll get another chance, but at the moment, it certainly won't be in Dallas."