The court challenge automatically cancels Mnangagwa's inaugartaion which had been scheduled to go ahead on Sunday the 12th of August.
After a whole week of press conference after press conference, the opposition party finally filed its papers with the Constitutional Court challenging the presidential result.
Zimbabwe's Justice Minister Ziyambi Ziyambi said President Emmerson Mnangagwa's inauguration that had been set for Sunday had been deferred after opposition leader Nelson Chamisa challenged presidential election results in court.
"If the MDC Alliance files before the deadline, then the Constitutional Court will have the final decision to stop the inauguration or allow it to be conducted within a period of 14 days".
The electoral commission declared the Zanu-PF's Emmerson Mnangagwa had 50.8% of votes against the MDC Alliance's Nelson Chamisa's 44.3%.
He said those who lost should accept the results and work hard to improve next time.
"Our legal team successfully filed our court papers".
It's amusing that Chamisa (MDC Alliance presidential candidate Nelson) entered an election wanting to win only.
"We have a good case and cause!" he tweeted shortly after filing the challenge.
The MDC arrived at the court less than an hour before it closed on Friday, the last day that the petition could be lodged.
Analysts say the legal challenge has little chance of success given the courts' historic tilt towards the ZANU-PF, which has ruled since independence from British colonial rule in 1980.
The legal team include Zanu-PF Secretary for Legal Affairs, Paul Mangwana, a veteran lawyer. Six died after soldiers opened fire on the protesters in a response the opposition alliance called "disproportionate and unjustified".
They said they were "deeply disturbed by continuing reports that opposition supporters are being targeted by members of the Zimbabwean security forces".
Mr Biti is the first senior opposition politician to be detained since Mr Mnangagwa took over from Mr Mugabe.