Police were called to street in Fazakerley following reports of a stabbing.
Officers were called to Haven Road by North West Ambulance Service staff at 9.14pm on Sunday.
A male, believed to be around 16 years old, has been taken hospital.
His condition has not yet been confirmed.
Merseyside Police has officers at the scene of the suspected attack, which was in a small estate off Longmoor Lane, close to the Shell garage.
A spokesman for the force confirmed police officers were dispatched to the site just after 9pm after being alerted to the injured boy by paramedics.
Officers were carrying out inquiries in the area tonight following the launch of an investigation into the circumstances surrounding the incident.
Anyone with information is asked to contact Merseyside Police by calling 101, sending a direct message on Twitter to @MerPolCC, or contacting Crimestoppers, anonymously, on 0800 555 111.
