While Nemat hit 78 off 246 balls, studded with 12 boundaries, Tiwary scored an unbeaten 75 off 213 deliveries with the help of seven fours and a six.
Jharkhand were dealt early blows after they elected to bat, as opener Bhavin Thakkar (14) and one-down batsman Ishank Jaggi (1) were dismissed cheaply.
But other opener Nemat, in the able company of Tiwary consolidated the innings.
The duo put on a solid 135-run stand together for the third wicket before Nemat got out.
For Gujarat, Jasprit Bumrah claimed two for 51, while Akshar Patel (1/26) and Rakesh Dhurv (1/50) took wicket apiece.
Brief scores:
Jharkhand 1st innings: 194 for five in 89.3 overs (Rameez Nemat 78, Saurabh Tiwary batting 75; Jasprit Bumrah 2/51) vs Gujarat.
