A two-time Pro Bowl wide receiver, Hopkins had his helmet knocked off by Ward during 1-on-1 drills in practice. Hopkins caught the ball before the two exchanged shoves, leading to punches thrown as multiple players attempted to intervene.
Hopkins and Ward likely will see each other again when the teams square off in a preseason contest on Saturday.
The 26-year-old Hopkins led the league with 13 touchdown receptions last season, with seven coming from quarterback Deshaun Watson. Hopkins also had 96 catches and finished fourth in the league with 1,378 yards.
A calf injury forced Hopkins to sit out the regular-season finale, the first game he has missed in his five years with the Texans.
Ward, 27, had 32 tackles and a forced fumble in seven games last season.