Struijk was sent off after 57 minutes of a Premier League match at the Stadium of Light on Saturday when he was ruled to have fouled Sunderland forward Wilson Isidor as he tried to run on to a through-ball.
Neither referee Thomas Bramall nor his assistants gave a foul initially, but VAR Neil Davies intervened and called Bramall to a screen by the side of the pitch.
After watching the replay several times, Bramall showed Struijk a straight red card for denial of an obvious goalscoring opportunity.
The decision, greeted with disbelief by Brighton players, has now been reversed by the Regulatory Commission following a successful claim of wrongful dismissal.
Brighton, 1-0 up at the time of Struijk's exit, went on to win 2-0 despite being a man down for a valuable away victory that left them third in the table, five points behind leaders Manchester City.
Struijk will no longer have to serve a one-match ban and will now be available to face Crystal Palace in the Premier League this weekend.
The 27-year-old joined Brighton from Leeds in a £20 million move in the summer, and was making his second league start for Fabian Hurzeler's side.
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