Lukaku received a second yellow card for provocative celebration after scoring a 95th minute equaliser from the penalty spot in the 1-1 draw a fortnight ago.
In a melee that followed Lukaku's sending off, Inter Milan goalkeeper Samir Handanovic and Juventus winger Juan Cuadrado were also dismissed by the referee.
Lukaku celebrated his goal by putting his finger on his lip in front of the home fans.
Lukaku's ban was upheld by Italy's Sports Court of Appeal but Italian Football Federation(FIGC) President Gabriele Gravina has intervened to overturn the ruling as an indication of the organisation's attempt to fight racism.
Gravina's decision to subsequently quash the verdict was warmly welcomed by Lukaku, who said in a statement on Inter's website: "I am really happy about this decision from the president of the FIGC, who has shown great sensitivity to the situation.
"I believe that thanks to his intervention, justice has been done and this sends out a great message to the whole world of sport and beyond. This has shown that the desire is there to fight racism."
The FIGC noted 'unequivocally that the behaviour of the player sanctioned by the match director followed the serious and repeated displays of hatred and racial discrimination by the opposing fans'.
"The measure reiterates how the fight against all forms of racism constitutes one of the founding principles of the sporting system," the statement added.
