William Ross Casement is the second man to appear in court in connection with the death of Enda Dolan.
Mr Dolan was a first year architecture student at Queen's University from Killyclougher.
The 18-year-old died after being struck by a van as he was walking along the Malone Road in Belfast in 2014.
He was returning to his student accommodation at Queen's Elms.
On Tuesday, 31-year old David Lee Stewart, from Grays Park Avenue in Belfast, admitted five charges arising from the death of Mr Dolan, including causing his death by dangerous driving.
Casement, 21, from Belvoir Drive in Belfast, appeared at Belfast Crown Court on Wednesday.
He admitted two charges - aiding and abetting dangerous driving, and aiding and abetting the failure to remain at the scene of an accident where an injury had occurred.
When both of the charges were put to Casement, he replied "guilty".
Casement was informed by Judge Gordon Kerr QC that he will be sentenced for the two charges on 22 April - the same day as his co-accused, David Stewart.

'Losing the Battle' was broadcast on BBC Radio Ulster on Sunday.
It examined issues including post-traumatic stress disorder, suicide, and attempted suicide among army veterans.
The programme heard claims that increasing numbers of veterans were facing difficulties accessing help to deal with mental health problems.
Brett Savage, 28, who celebrated his 19th birthday in Afghanistan, said: "I didn't expect my life to be like this now. Never. You know I can't sleep and stuff. Stupid things remind me of things."
Alexander Gore described the changes he has faced since a homecoming parade in Belfast for soldiers returning from Iraq and Afghanistan.
He said it was "definitely a proud moment in my life" but that after it "things just started to go downhill with the post traumatic stress really".
"Now it is never going to go away, it is always going to be there and everybody is going to need help sooner or later with it," he added.
Aaron Nixon, now 25, said he had to pay for a private post-traumatic stress disorder (PTSD) assessment at a Belfast clinic this month.
He explained how he suffered a gunshot wound to his leg in Afghanistan.
"I lost five inches of my bone," he said.
"I had five years of limb reconstruction. About 30 surgeries."
While some of the veterans, from various conflicts at home and abroad, are actively seeking medical help themselves, others are turning to charities including the independent  Beyond The Battlefield which is based in Newtownards, County Down.
Speaking in the documentary, its chairman Robert McCartney outlined stark details about one six-month period at the centre.
He said: "These guys come back and they don't know what is wrong with them.
"They get into trouble with their families.
"They have lost everything, and the last attempt that they will do, is suicide.
"We have had 260 through here from April and I would say out of that 260, at least 50% have attempted some type of suicide."
Andy Allen, now an MLA at Stormont, lost both his legs after being injured by a Taliban improvised explosive device in 2008.
He now helps to run AA Veterans Support in north Belfast.
He said that after they started providing the counselling services, they saw an increase from reserve personnel, "as well as individuals that served in Afghanistan and other conflicts".
He added: "It's my belief and indeed 'AA Veterans Support' have pushed for it from day one, that we need a respite training centre here, dedicated to the needs of our service personnel, veterans and their families.
"A one stop shop that will be able to provide all of the services under the one roof."
The programme also detailed ongoing problems with the implementation of the Armed Forces Covenant in Northern Ireland.
Jonny Rollins, a retired army colonel who is now the local representative of the Confederation of British Service Charities, explained that a key part of the covenant cannot be implemented in Northern Ireland because local councils do not have the same powers as councils in other parts of the UK.
"The core of the Armed Forces Covenant to date has been a thing called the community covenant designed to be signed by local authorities who have levers over the provision of education, health and housing and local authorities here don't have that," he added.
'Losing the Battle' was broadcast on BBC Radio Ulster on Sunday but is available on the BBC iPlayer.
A south Belfast man has admitted offences linked to the death of a County Tyrone student who died after being struck by a van.
[NEXT_CONCEPT]
A Northern Ireland charity is helping more than 100 army veterans who have tried to take their own lives, a BBC documentary has been told.