The leaders had been taken to the Kingsway Camp Police Station by the Delhi Police as they marched to the the Rashtrapati Bhavan to protest against unemployment, inflation and price rise.
Other leaders, including Harish Rawat, P Chidambaram, and Deepender Hooda, had also been detained.
Gandhi earlier slammed the Bharatiya Janata Party (BJP) and the central government over price rise. Addressing the media, Gandhi said that there is an "onset of dictatorship in India" and that the RSS is now "controlling all independent institutions."
Congress leader Rahul Gandhi, wearing black clothes, with party MPs during a protest march towards Rashtrapati Bhawan as part of party's nationwide protest over price rise, unemployment and GST hike on essential items.
Several Congress MPs, including Rahul Gandhi, wore black to the Parliament as a mark of protest
Congress MPs from both the Houses met at 10 am at Congress Parliamentary Party (CPP) Office
Section 144 of the CrPC has been imposed in the New Delhi district, barring Jantar Mantar
The Delhi Police said, "Protest/dharna/gherao in the area of New Delhi district on 5 August cannot be permitted in view of security, law and order, traffic reasons"
Speaking on the ED's probe after the agency sealed the office of Young Indian at the National Herald office, Congress leader Rahul Gandhi said on Thursday that it was an intimidation attempt by the Narendra Modi-led government
Congress Leaders Released After 6 Hours in Detention
Congress leaders, including Rahul Gandhi and Priyanka Gandhi Vadra, were released from the Kingsway Camp Police Station after spending six hours in detention.
'335 Protesters, Including 65 Cong MPs Detained': Delhi Police
The Delhi Police said that a total of 335 protesters, including 65 Congress MPs, were detained by them amid protests on Friday.
The police added that despite repeated warnings that Section 144 was in place, Congress leaders and workers still undertook their protest.
"When the police moved in to contain the situation, the protesters tried to obstruct the police officers from performing their duties, manhandled and injured them. Appropriate legal action is being taken into the matter," Special Commissioner of Police Sagar Preet Hooda said in a statement.
'Thousands' of Maharashtra Cong Workers Detained
Several Maharashtra Congress workers were detained by the police in Mumbai ahead of their planned agitation against the Centre
The party claimed that thousands of its workers were detained across the city on Friday.