DiBiase made his WWE television debut as a villain on May 26, 2008, where he cut a promo about his intent to become a champion like his father, Ted DiBiase, Sr., challenging the World Tag Team Champions, Cody Rhodes and Hardcore Holly. At the Night of Champions pay-per-view, DiBiase won the World Tag Team Championship in his first match in WWE, after Rhodes betrayed Holly, revealing himself to be DiBiase's partner. After holding the titles for just over a month, they dropped them to John Cena and Batista on the August 4 episode of Raw. The following week, DiBiase and Rhodes used their rematch clause to regain the titles.
DiBiase and Rhodes were soon joined by Manu, forming a stable of multi-generation superstars. On the October 27 episode of Raw, DiBiase and Rhodes lost their titles to CM Punk and Kofi Kingston. It was during this time that Randy Orton became linked to Rhodes, DiBiase, and Manu on television, criticizing them in a mentor-type role. On the November 3 episode of Raw, DiBiase was attacked by Orton, after he interfered in Orton's match.
On the January 12, 2009 episode of Raw, DiBiase returned to aid Manu and Sim Snuka in attacking Cody Rhodes and Randy Orton. Instead, however, DiBiase turned on them and helped Rhodes and Orton assault Manu and Snuka, thus joining The Legacy faction. As part of The Legacy, DiBiase entered the Royal Rumble match in order to help Orton win, and lasted until the final four, before being eliminated by Triple H. Rhodes and DiBiase became then involved in Orton's scripted rivalry with the McMahon family, helping him attack Shane and Stephanie McMahon, and Stephanie's real-life husband, Triple H. DiBiase was also elevated to main event status as a result of joining The Legacy, competing in handicap and six-man tag team matches, as well as the occasional singles match against Orton's opponents and rivals. On April 26, at the Backlash pay-per-view, DiBiase, Rhodes, and Orton defeated Triple H, Batista, and Shane McMahon in a six-man tag team match, which, per the pre-match stipulation, resulted in Orton winning the WWE Championship. During WWE's tour of Australia in early July, DiBiase suffered an arm injury, but did not miss any time because of it. Throughout mid-2009, DiBiase and Rhodes continued to compete against and attack Orton's rivals, particularly Triple H, preventing him from earning a match for Orton's championship. As a result, Triple H reformed D-Generation X (DX) with Shawn Michaels, and they defeated DiBiase and Rhodes at SummerSlam. DiBiase and Rhodes later defeated DX in a submissions count anywhere match at the Breaking Point pay-per-view, before losing to DX in a Hell in a Cell match at the Hell in a Cell pay-per-view in October.
Tension between the members of The Legacy began building in 2010, when Orton attacked DiBiase and Rhodes for accidentally costing him a chance to win the WWE Championship at the Royal Rumble pay-per-view. In February 2010, DiBiase defeated Mark Henry in an Elimination Chamber qualifying match, earning a chance to win the WWE Championship. At the Elimination Chamber pay-per-view, he eliminated Orton from the Elimination Chamber match, but was eliminated by Kofi Kingston soon after. On the February 22 episode of Raw, Orton turned on The Legacy, believing they had a plan to turn on him, and in retaliation, they attacked Orton the following week. As a result, the three competed in a triple threat match at WrestleMania XXVI, in which Orton defeated Rhodes and DiBiase.
On March 27, 2010, DiBiase and his brother Brett inducted their father into the WWE Hall of Fame.
After WrestleMania, DiBiase debuted a new gimmick of an arrogant millionaire, similar to his father's old gimmick. On the April 5 episode of Raw, DiBiase was given possession of the Million Dollar Championship and access to a trust fund by his father. DiBiase then began looking for a "Virgil", a manservant like his father used to have. He offered the position to R-Truth, who refused, provoking a feud between the two. On the May 17 episode of Raw, DiBiase revealed his "Virgil"—the original Virgil who had worked for his father. In his first singles pay-per-view match at Over the Limit, DiBiase was defeated by R-Truth. During the match, DiBiase suffered a concussion, but was able to appear on Raw the following night. On the June 21 episode of Raw, DiBiase fired Virgil in favor of the managerial services of his on-screen girlfriend Maryse. In September 2010, DiBiase entered in a feud with Goldust over the Million Dollar Championship, after Goldust stole the title from him. On the November 15 episode of Raw, Goldust returned the Million Dollar Championship belt to DiBiase Sr., who then offered to give it back to his son, but he refused the offer, proclaiming that he was interested in another belt. Later in the night, DiBiase attacked WWE United States Champion Daniel Bryan, setting up a match at Survivor Series for the championship, in which he was unsuccessful. DiBiase was a Pro for the fourth season of NXT, in which he and Maryse mentored Brodus Clay. On the January 25, 2011, episode of NXT, Clay traded DiBiase for Alberto Del Rio as his Pro.
As part of the 2011 supplemental draft on April 26, DiBiase was moved to the SmackDown brand. In his first match on SmackDown, DiBiase lost to his former tag team partner Cody Rhodes. The following week, DiBiase was accompanied to the ring by Rhodes. On the June 3 episode of SmackDown, DiBiase lost to former rival, Daniel Bryan via submission. After the match, Rhodes and DiBiase attacked Bryan, but were stopped by Sin Cara. On the July 8 episode of SmackDown, DiBiase teamed with Rhodes in a winning effort against the team of Bryan and Ezekiel Jackson. After DiBiase lost a match against Randy Orton on the August 26 episode of SmackDown, Rhodes attacked him, ending their association.
On the September 16 episode of SmackDown, as Rhodes was ridiculing the audience, DiBiase disguised himself as a fan by wearing a paper bag on his head before attacking Rhodes, turning into a fan favorite. DiBiase then challenged Rhodes for the WWE Intercontinental Championship at Night of Champions, but was unsuccessful. In a YouTube video published on September 22, DiBiase introduced his new gimmick to hold tailgating parties with fans just before WWE events, terming those who tailgated with him as the "DiBiase Posse".
In November 2011, Jinder Mahal chastised DiBiase about forsaking his wealthy upbringing to hang out with commoners, starting a feud and leading to DiBiase defeating Mahal on the December 9 episode of SmackDown. Three weeks later, Mahal defeated DiBiase to conclude the feud. In January 2012, Hunico started a feud with DiBiase when Hunico was offended that he was not invited to one of DiBiase's Posse parties. Both traded victories in regular singles matches on SmackDown, with DiBiase wrestling despite a wrist injury. Although DiBiase beat Hunico in a flag match, Hunico cheated to win the last match in the series in February. On March 6, DiBiase suffered a broken ankle during television tapings. That same month, DiBiase announced that he was undergoing shoulder surgery. DiBiase returned on September 16 at Night of Champions, participating in the pre-show WWE United States Championship number one contender battle royal, but was eliminated by Tensai.
DiBiase's only televised match in 2013 saw him defeat Michael McGillicutty on the May 9 episode of Superstars. On August 26, DiBiase announced that he was not renewing his WWE contract, which expired on September 1.