Despite being one of the smallest forwards in the competition, at 1.78m and 94kg, Tevaga continues to play well above his weight.
"We're thrilled to have Jazz signed for two more seasons," said Warriors head coach Stephen Kearney.
"He brings so much to our group with his energy on and off the field. He isn't the biggest forward going around by a long way but that doesn't bother him. What he offers is intensity and enthusiasm either starting or coming off the bench. He certainly gives us tremendous value and it's wonderful having him around the club."
After being used in a utility role for most of 2019, Tevaga was given the opportunity to start when regular Lachlan Burr was rested for the clash against Penrith in round 15.
Tevaga responded by making 184 metres from 21 runs along with 50 tackles and backed it up with another impressive 56-minute stint against Newcastle (114 metres from 11 carries plus 39 tackles).
He played the full 90 minutes in last weekend's 18-18 extra-time draw with the Broncos when he made 184 metres from 22 runs, as well as a staggering 72 tackles.
Tevaga was originally signed following an NYC open trial in 2013, going on to make his under-20 (then NYC) debut in 2014.
He played 20 times that year including the grand final when the Junior Warriors won the premiership for the third time.