Video that has gone viral on social media shows the female police officer being knocked to the ground and kicked, while others show vehicles being turned over and vandalised.
The two victims were among several officers who were called to a warehouse party on an industrial estate in Champigny-sur-Marne, east of Paris, on New Year's Eve.
It had been organised on social media and several hundred people turned up, some reportedly from outside the area.
The police were called when would-be revellers who had been denied entry started to attack the building, according to organisers.
When police tried to keep the two groups apart, the pair were separated from their colleagues and attacked.
The man received a broken nose and a sprained wrist and the woman suffered bruises to her face and temporary deafness.
Police and emergency service vehicles were attacked and the police fired teargas.
The organisers had not applied for official authorisation, according to the town's Communist deputy mayor, Christian Fautré, who condemned a "cowardly assault" in a statement.
Two people were arrested in connection with the vandalism but on Tuesday nobody had been detained over the attacks.
Police said they hoped to find the culprits by viewing the videos.
Ministers, opposition denounce "lynching"
The assaults have created an outcry, with right-wing politicians calling for tougher law-and-order policies.
Local MP Gilles Carrez, a member of the right-wing Republicans party, called for more personnel for the town's police force but also said it could have happened anywhere.
Les coupables du lynchage lâche et criminel des policiers faisant leur devoir une nuit de 31 décembre seront retrouvés et punis. Force restera à la loi. Honneur à la police et soutien total à tous les agents bassement agressés.Emmanuel Macron (@EmmanuelMacron) 1 janvier 2018
In a tweet on New Year's Day President Emmanuel Macron vowed that the perpetrators of the "cowardly lynching" will be "found and punished".
Interior Minister Gérard Collomb echoed his words after meeting the officers who had been assaulted.
"Attacking the security forces is attacking our republic," he tweeted.
Interior minister vows to catch assailants
#Champigny : je viens de m’entretenir avec les fonctionnaires de Police agressés.Gérard Collomb (@gerardcollomb) 1 janvier 2018
Tout est mis en œuvre pour que les lâches auteurs de ces actes inqualifiables soient appréhendés et condamnés.
S’attaquer à nos forces de sécurité, c’est s’attaquer à notre République.
The Republicans' newly elected leader, Laurent Wauquiez, attacked the government's plan to introduce a form of community policing in February and called for "tough action".
And Marine Le Pen, of the far-right National Front, claimed that some parts of France were subject to a kind of "urban guerrilla warfare" and called for "presumption of legitimate defence" for police and gendarmes.
Police unions expressed shock at the attack.
They called for more resources and the reintroduction of minimum sentences for attacks on police, a measure that was scrapped under the previous, Socialist, government.
More attacks on police
Another police officer was assaulted in Aulnay-sous-Bois, also near Paris, on New Year's Day when he and a colleague tried to stop youths who had allegedly stolen a motorbike.
Aulnay was the scene of riots folloiwing the alleged sexual assault by police on a young man last year.
In all, eight police officers, four gendarmes and three soldiers on anti-terror patrol were injured on New Year's Eve, according to official figures.
A total of 1,031 cars were torched across France - up from 935 a year ago - while arrests rose from 456 to 510, the interior ministry says.
Official figures show that 5,767 police officers were injured during the course of duty in 2016.
The figure is rising, notably for attacks with firearms.
While declaring such attacks "unacceptable", Collomb also blamed social conditions in "pauperised" and "ghettoised" areas.
"I was in Champigny yesterday," he told Europe 1 radio on Tuesday. "When you see the tower blocks, you say to yourself that there is a totally inhuman aspect that can only generate violence. We need fundamental reforms in urban development policy."