The injured pitcher, who has been on the disabled list since March 21 with a pinched nerve in his right arm, threw 25 pitches, including fastballs, changeups and sliders, in one inning of work on Wednesday. Paulino threw to hitting coach Sean Berry and outfielder Michael Bourn.
"I'm feeling great today about my first time," he said. "All my pitches were working great. I just tried to put the ball over the plate, but to throw strikes was even better."
Paulino will throw one more practice session on Saturday, probably the same length, before being sent to the Minor Leagues for a rehab assignment.
"He threw well," said Astros manager Cecil Cooper. "A couple of hitters who got in there against him said the ball was really coming out of his hand. I'm very impressed with what I saw today. Now we just need to get to step two."
Paulino said the lack of pain was the best sign for him that he is ready to take the mound again.
"I had a little complaint about my mechanics, but that's fine because it's my first time to do the motion of the game. I'm happy though."
Krysten Oliphant is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.