Shannon Thompson, who lives in an interface area, had gone to a fast food outlet with friends on Tuesday night prior to the attack.
They were walking along Ballymacarret Road at about 9.30pm when a group of youths approached them.
A police spokesperson said: "One of the male youths then struck one of the girls, aged 15, in the face with a wooden object, then made off on foot.
"The girl was taken to hospital and treated for cuts and bruising to her face."
Shannon said that she remembers hearing her friends screaming behind her.
She said that she then was hit on the face with a plank of wood and woke up feeling "really scared."
"It happened so fast - I blanked out and didn't even know what actually happened. I woke up and saw blood everywhere, and my eye [was] swelling up."
One of Shannon's friends took her to her house to clean her up while they waited for an ambulance.
She was taken to hospital to check for any possible fractures. While there was none detected by medics, the teenager has been left with a badly swollen face, and closed over eye.
Shannon's family believe her attackers are from the nearby Catholic Short Strand.
Her mother Rosey told UTV the assault has left her feeling "so angry and so upset".
She said that she has been left "hurt" by the incident and can't get the image of her daughter's injured face out of her mind.
The worried mother said that items are constantly being thrown over the interface into the backs of people's gardens.
"Golf balls - anything they can get their hands on," she said.
Local representatives said that there's been ongoing trouble at the interface in recent weeks.
Ulster Unionist Party MLA Michael Copeland said that he reacted to news of the attack with a mixture of "compassion, concern and a degree of anger."
"People who live in the shadow of peace walls pay a very heavy price for the presence of those walls which divide people who've a good deal in common and a good deal that separates them.
"The difficulty is that Shannon lives in a house where she doesn't feel safe."
East Belfast MP Naomi Long has called on all those with influence in the local community to help bring an end to ongoing violence at the flashpoint.
The Alliance politician said: "No-one wants to see this ongoing violence, which does nothing but cause harm to the people and businesses in the area. If it continues, it could end up in even worse situations than the one which saw this poor girl attacked.
"The time for leadership is now. OFMdFM set out their stall in their Together: Building a United Community strategy but have yet to show any real, effective leadership in improving community relations, meaning progress in the area is immensely slow.
"Alliance will continue to work to create a truly shared future but we are also calling on all those who have influence in this area to join us in helping end this destructive behaviour."
Niall Ó Donnghaile, Sinn Féin councillor for the area, has condemned the attack.
"All incidents at the interface which bring hurt, injury and trauma are to be utterly condemned without reservation.
"News of last night's attack is another incident, in a series of incidents that have been orchestrated and carried out by gangs of youths on both sides of the interface for weeks now," he claimed.
"This is a danger I have consistently highlighted both publicly and privately and strenuously warned about the dangers involved with young people being caught up in these pre-planned events," he continued.
"Anyone with any information on last night's attack on this young girl should bring it forward to the PSNI, because it is they who now need to act on bringing an end to these violent incidents.
"The reality of all of this is that it's our neighbours on both sides of the interface who are left to pick up the pieces. Last night's attack in no way represents the people of the Short Strand and my thoughts are with the young girl concerned and I wish her a very speedy recovery."
Police confirmed that they are treating the attack as a sectarian hate crime and are appealing for any witnesses to come forward.
A spokesperson added that the attacker was described as being around 16 or 17 years old, 5ft 7inches tall with brown hair, and was wearing a white, red and blue coloured tracksuit.