The girl, who is 14 years old but cannot be named for legal reasons, was set to appear in court on Friday afternoon.
Meanwhile, the victim of the alleged attack has been named by police as Nimroy Hendricks.
Mr Hendricks was found with stab wounds to the chest in Russell Way in Crawley, West Sussex, on Tuesday.
He died at the scene after being treated by paramedics and an air ambulance doctor.
“The circumstances of this case are particularly challenging for everyone involved and will continue to be difficult as people come to terms with significant loss and grief,” Detective Chief Inspector Andy Wolstenholme, from the Surrey and Sussex Major Crime Team, said on Friday.
“It is imperative that the criminal justice system is allowed to operate effectively in order to support all involved in this case…” he added.
“Therefore, I would make a personal plea to people to not speculate on social media on the circumstances of the case or the identity or motivation of the defendant, whose name may not legally be published.”
Mr Hendricks was described in newspaper reports on Thursday as a carer who looked after elderly people with mental health issues.
A 21-year-old man from London was also arrested by police last night on suspicion of assisting an offender in connection with the incident.
Additional reporting by PA