The landmark challenge has been launched by two couples - Grainne Close and Shannon Sickles and Chris and Henry Flanagan-Kanem.
They have been granted permission to judicially review the Stormont Assembly's repeated refusal to legislate for same sex marriage.
They were the first and second couples, respectively, to enter into a civil partnership in the UK after Northern Ireland made that option available in late 2005.
Mr Justice Treacy at Belfast High Court will hear the case.
Northern Ireland is the only part of the UK or Ireland where civil marriage is denied to gay couples, following the Republic of Ireland's 'yes' vote in a referendum in May.
The issue of same sex marriage was debated for the fifth time last month.
The majority of MLAs voted in favour of introducing gay marriage however despite this the proposal fell because unionists who oppose the move deployed a controversial voting mechanism to effectively veto the decision.
In early 2015, around 20,000 campaigners staged a march through Belfast city centre demanding a change in the law.
A number of human rights group have spoken out, including Amnesty International, which has described the case as "hugely significant".
Patrick Corrigan, Amnesty's Northern Ireland programme director, said: "Success in this case could have positive implications for thousands of other couples in Northern Ireland.
"Following the repeated failure of the Northern Ireland Assembly to legislate for marriage equality, couples have been forced into the courtroom to demand equal treatment before the law.
"It is unacceptable that they have been obliged to sue the Government in order to have what the rest of society takes for granted - for the State to recognise their right to get married.
"With politicians having abdicated their responsibility to deliver equal treatment for same-sex couples, it is now over to the courts."
