"Hey Twitter world, this is yours truly. Coming soon to Twitter, you'll get to read all my thoughts and opinions on just about everything," Simpson said in a selfie video tweeted Friday night.
Simpson lawyer Malcolm LaVergne confirmed to CNN that the account was authentic, as was the video, that is filmed by Simpson on a smartphone in the yard of his Las Vegas residence.
Simpson's Twitter account - @TheRealOJ32 - refers to his jersey number he wore as a star running back at the University of Southern California and then with the National Football League's Buffalo Bills.
Just after his first tweet thousands of people flooded his post with reactions, comments and memes.
"You really said 'coming soon' like it's a new Harry Potter movie. I can't," a Twitter user wrote.
Not only did Simpson quickly gather over 4 million followers, but his video also garnered more than 80,000 likes.
"I hope that you are making some progress in identifying the real killers," to which someone replied, "He makes progress by looking into the mirror every morning," a person said.
Another said, "The twitter account nobody asked for."
Someone else added: "Hey OJ. Big Fan. I'm in need of a pair of gloves. What's your favorite place to purchase them from?"
In his second tweet, Simpson said in a new video he wants to "set the record straight." Which record? He didn't say.
( With inputs from IANS )