Jared Rosser and Elliot Dee grabbed tries and Jason Tovey a late penalty before Sam Davies saw a last minute penalty fly wide as Dragons held their nerve.
And Jones hailed the resolve of his players as they bounced back from heartbreak in Cardiff before Christmas to secure a first Welsh league derby win since Boxing Day 2014.
“It was a big defensive display and the boys worked really hard for each other,” he said.
“I actually thought we could have played better in the first half and controlled it more, but Jared (Rosser) got us the breakaway try.
“It was about huge heart, we put it on show for each other and we backed up last week’s performance.
“It was a great kick from Tovs (Jason Tovey) to come up late on and take that. The Sam Davies penalty I actually thought it was a 50/50 decision against Jared.
“My heart was in my mouth a little bit because I thought it was going to go the same as last week. But we held out and it is a big win for us.
“It’s a results business and that is what it is at the top end. We felt we deserved two points last week and we won tonight – it is fine margins.
“Your defence reflects attitude – the boys are working hard for each other and we showed that. That shows that they are prepared to play for each other.
“The players have been making steps all year long. It is 100% down to them, they are doing a really good job and I couldn’t be prouder of them.”
Jones also hailed the impact of the crowd as over 7,000 packed into Rodney Parade and generated a superb atmosphere.
“You could hear the crowd - probably back in Usk where I come from,” smiled Jones.
“They were loud today. Rodney Parade is a proper rugby ground and when we put that sort of performance out the region can be proud.
“We’re very pleased for them and we hope they return and keep backing us the way they have today.”
Dragons now travel to Parc y Scarlets next Saturday evening to face Scarlets and Jones added: “We’ll go down there with confidence from the last few performances.
“We know the size of the task ahead, but we will go to give a good account of ourselves.”