At around 11.55am on Saturday 9 November outside a café at Wendover Woods, a girl, aged 2, was hit by a male causing her to fall forward and hit the ground face first.
She sustained bruising to her forehead and face but did not require hospital treatment.
The offender is described as a young male, either a young adult or teenager of stocky build.
No arrests have been made.
Investigating officer, PC Hannah Phillips based at Aylesbury police station, said:
“We are appealing for witnesses to this incident.
“It happened in a relatively busy area during the day and we believe this could have been seen by a number of people.
“If you have any information about this incident, please get in touch on the non-emergency number 101 or make a report online quoting the reference 43190351479.
“You can also contact the independent charity Crimestoppers, 100% anonymously on 0800 555 111.”