A man who allegedly assaulted Brisbane bus passengers in separate attacks late last year has been charged with two more counts of assault.

Key points: The man was arrested and charged on Tuesday with two counts of assault

The man was arrested and charged on Tuesday with two counts of assault Overnight, police charged him with two more counts and he's facing court today

Overnight, police charged him with two more counts and he's facing court today A 16-year-old and 65-year-old woman were both allegedly attacked by the same man in separate incidents

Brett James French, 39, was picked up by police on Tuesday afternoon while walking on Lutwyche Road on Brisbane's northside.

It has been alleged a 16-year-old boy was walking down the street when Mr French punched him once in the face in an unprovoked incident at Ashgrove in September last year.

A 65-year-old woman was also allegedly punched in the face in a separate incident at Red Hill in November.

Mr French, from Aspley, has been charged with one count each of assault occasioning bodily harm and serious assault.

He faced the Pine Rivers Magistrates Court today and was denied bail.

The magistrate described Mr French's crimes as "unprovoked and cowardly" and said he could still be a danger to the community if released.

He is also facing two counts of assault occasioning bodily harm for two other alleged assaults, where a 40-year-old man and 18-year-old woman received facial injuries in two separate attacks on buses in December last year.

Police said the injuries suffered by the victims were significant enough to cause bruising, swelling and pain.

Investigators continue to appeal to anyone who may have been a victim of a random or unprovoked assault in Brisbane by a man, and who has not already spoken to police, to please contact them.

Both matters will return the Brisbane Magistrates Court in February.