Dragons had already chalked up three wins in the competition to date and made sure they remained in top spot at the mid-season break as they eased away in the second half at Ystrad Mynach.
RGC went ahead in the eighth minute courtesy of wing Dafydd Williams but back came Dragons with Ewan Rosser, fresh from his recent hat-trick against Ospreys, darted over.
Wing Carrick McDonough put Dragons clear before a converted Joe Coope-Franklin score made it 17-12 at the interval.
RGC continued to battle to score three tries in the game, but further efforts from Morgan Richards, Brodie Coughlin and Dylan Davies wrapped up maximum points.
Timeline:
08m D Williams t 0-5
11m Rosser t 5-5
16m McDonough t 10-5
20m Jones t Earl-Jones c 10-12
34m Coope-Franklin t Reed c 17-12
45m Richards t Morgan c 24-12
48m Jones t Earl-Jones c 24-19
51m Earl-Jones p 24-22
60m Coughlin t Morgan c 31-22
63m Davies t 36-22
Dragons: 15 Lewis Bates (Richards 41), 14 Ewan Rosser, 13 Jonny Paynter (Owen 43), 12 Ollie Stansfield, 11 Carrick McDonough, 10 Will Reed (Morgan 41), 9 Dylan Davies; 1 Henry Hibbs (Dowse 49), 2 Brodie Coughlin (Wakeley 67 49), 3 Clay Gibbons, 4 Callum Oliver (Thompson 67), 5 Ben Carter, 6 Matthew Jeffries, 7 Joe Coope-Franklin (Howard 51), 8 Ben Torjesen
Replacements: 16 Jack Wakeley, 17 Aaron Dowse, 18 Owen Peddle, 19 Chris Thompson, 20 Ollie Howard, 21 Jake Morgan, 22 Anuerin Owen, 23 Morgan Richards
Dragons Under-16s Red (formerly known as North) drew 14-14 with RGC Under-16s at Parc Eirias on Sunday. Wing Will McCrudden and centre Oli Andrews scored for Dragons, with the second half scoreless.
