They happened just hours apart on Marsh Way on Friday and both involved a pedestrian and a car.
Police were called to the first collision, involving a silver Vauxhall Corsa, just before 7.10am.
The pedestrian, a 55-year-old man, suffered a serious leg injury.
Just over ten hours later, at around 5.35pm, officers were called to Marsh Way again, near to the bus station after a teenage boy was hurt.
A West Yorkshire Police spokesperson said: "A white Suzuki Ignis was travelling along Marsh Way towards Wakefield.
"A pedestrian was crossing the road and there was a collision between the pedestrian and the car.
"The 16-year-old male victim suffered serious injuries and was taken first to Pinderfields Hospital but then transferred to Leeds General Infirmary for medical treatment."
The boy remains in hospital.
Enquiries are on going and police are now appealing to members of the public to come forward if they witnessed either of the collisions.
Anyone with any information is asked to contact police via 101 quoting log number 323 (the earlier incident) or log number 1512 (the later incident) of August 4.