The incident happened around 11pm on Friday in Westmuir Street.
A 29-year-old motorcyclist has been taken to hospital and is in a critical state.
The driver of the van did not sustain any injuries.
A Police Scotland spokesperson said: "At around 11.10pm on Friday 25th September, we received a report of a serious crash involving a van and a motorbike on Westmuir Street at the junction of Hart Street around.
"The 29-year-old motorcyclist was taken to Glasgow Royal Infirmary, where he is described as critical.
"The driver of the van was not injured. The road was closed for five hours."
"Enquiries are continuing."