Matt Baggott told the Northern Ireland Affairs Committee on Thursday that ongoing protests are "stripping out district policing".
So far 174 people have been arrested and 124 charged after disorder following loyalist flag protests. Demonstrations began in December after a Belfast City Council voted to reduce the number of days the flag is flown at city hall.
"I think we need to review again, in the light of the last six months of protest followed by protest followed by protest, the level of resourcing we have," Mr Baggott said.
"We are no longer 15,000 strong, plus the army. We are 7,000 strong and tackling a significant threat from terrorism, dissident republicanism, dealing with organised crime, managing public protection, delivering personal policing.
"I want those police officers delivering neighbourhood policing and all the things that go with a modern police service that's operating in a democratic framework."
On Wednesday, a senior PSNI officer said more than 70 PSNI officers are investigating nearly two months of disorder throughout the region, and said the force is moving towards arresting people at the scene of illegal protests or disorder and bringing them quickly before the courts.
Looking forward over the next two or three years, judging that against the way in which we've seen the last six months unfold, I think it's inevitable we will need to have more police officers.
Chief Constable Matt Baggott
The Chief Constable told the committee that there had growing tension in relation to a number of issues including parading.
He says that had PSNI been "over-zealous" from the beginning of the protests, it may have only provoked more people onto the streets.
It was also revealed this week that two senior officers from London Metropolitan Police who policed the summer riots there in 2011 have been brought in to help with the investigations.
Mr Baggott said there was a danger in comparing the riots that have broken out in Northern Ireland with the rioting in London.
"I think the similarity there was the role social media played in galvanising large numbers of people onto the street very quickly," he said.
"But they are so different, so much as to be incomparable."
Terry Spence from the NI Police Federation told MPs that the 7,000 strong force deemed apt under the Patton review was not appropriate in the current political climate and called for an extra thousand officers.
"We don't have any semblance of a peaceful scenario," he said.
"The threat level has been described by the chief constable as at the upper end of severe and we have these murders taking place, we have loyalist paramilitaries who are much more active and pose a real threat to the peace process.
"Both loyalist paramilitaries and dissident republicans have been engaged in murder, in the last twelve months so it's not getting better anytime soon and that's why we believe that we need these resources urgently."