The move comes two days after the Texans released two-time Pro Bowl tight end Owen Daniels.
Graham was drafted by the Texans in the fourth round of the 2010 draft. He has appeared in 41 games with 20 starts in his four-year career.
He took over as starter last season when Daniels was injured and started a career-most 11 games. The 27-year-old had 49 receptions for 545 yards and five touchdowns last season, which were all career-highs.
The team did not provide terms of the deal.