A man appeared at West Kowloon Court on Wednesday on suspicion of publishing seditious posts on social media.
The 57-year-old suspect is accused by national security police of repeatedly publishing seditious posts on social platforms inciting hatred towards Hong Kong and central authorities, and inciting violence.
He was charged with "knowingly publishing publications that had a seditious intention".
The man was not required to enter a plea and was remanded in custody.
The case has been adjourned to December 30.
The suspect was arrested in Hung Hom on Tuesday.