Colorado had lost four out of five on the heels of an eight-game winning streak, but came back from an early deficit to keep starting pitcher Juan Nicasio unbeaten for the season.
Nicasio (3-0) gave up three runs, one of them earned, on four hits in five innings. Rafael Betancourt earned his eighth save with a perfect ninth.
Colorado scored twice in the first, but Arizona owned a 3-2 lead heading into the fifth.
Tulowitzki, however, came through with a double to deep left that cleared the bases and gave the Rockies the lead for good.
Wilin Rosario finished off the scoring by leading off the Colorado sixth with a homer.
Arizona had won three in a row.