The pair, both signed to Roc Nation, the management agency and record label owned by rapper Jay-Z, were seen enjoying each other's company, fueling speculation about their relationship.
Although Megan recently attended an Inter match, there is no official confirmation that she is dating Lukaku, who recently ended his five-year relationship with Sarah Mens.
The presence of both artists at the wedding suggests a connection through their shared association with Roc Nation, but the exact nature of their relationship remains undisclosed.
Megan Thee Stallion, 28, had been in a relationship with rapper Pardison Fontaine for over two years, but breakup rumours surfaced in February after she unfollowed him on social media.
On the other hand, Lukaku, 30, has kept his personal life largely private.
However, he recently revealed that he has a second son named Jordan, who is one year old, in addition to his five-year-old son Romeo.
While it remains uncertain whether Lukaku and Megan attended the wedding of Inter forward Lautaro Martinez as a couple, they were undoubtedly in esteemed company.
Reports suggest that Lionel Messi and his wife Antonela Roccuzzo may have also been present at the ceremony, given their close relationship with Martinez as Argentina teammates.
The lavish wedding took place at a five-star hotel in Como, Italy, and attracted more than 120 guests. Martinez, 25, exchanged vows with Agustina Gandolfo, an Argentine model who happens to be one year older than the talented striker.
The ceremony was attended by several other Inter and Argentina teammates, including the charismatic goalkeeper Emiliano Martinez.
Meanwhile, Lukaku is currently preparing for the UEFA Champions League final against Manchester City, which is set to take place on Saturday, June 10.