Her boyfriend Brandon Mehmed posted on Instagram on Friday night to say "she is safe and well".
It tweeted: "We had appealed for help to locate Marina Joyce, 22, reported missing from Haringey".
Police urge anyone who can help find Marina to call 101 and quote 19MIS031063.
If you didn't know, Marina was previously involved in the infamous conspiracy theory after she posted a video in 2016 where fans thought she was whispering "help me" and appeared to have bruises on her arms.
The caption on the video claimed there would be another video a week later but nothing else was released online.
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"It was reported she was last seen on 31 July".
The Metropolitan Police have now appealed to the public for information as part of its investigation.
The 22-year-old YouTuber went viral back in 2016 after peculiar behaviour in videos and on social media had fans anxious she was struggling with drug abuse, or was being held against her will.
In 2016, Joyce told fans that she was in a "dangerous place" and asked for help, prompting speculation on social media that she could have been kidnapped.
The hashtag #SaveMarinaJoyce began trending on Twitter in the United Kingdom and USA, which lead to the police getting involved at the time.
Ms Joyce has over 2.1million subscribers on YouTube and 286,000 followers on Instagram.
Another time she caused fans to worry for her well-being when weeks later she asked fans to call her "Goddess Marina", saying she wanted to create a temple where she would be known as "God of the Shrine".