It's the second time within a week that Obama's approval rating has sunk below 40 percent in a major poll.
Quinnipiac recorded its lowest level of approval since Obama took office in 2009.
Similarly, a record high, 52 percent, believe Obama is not honest or trustworthy, up 3 percentage points since May.
Majorities of voters also believe Obama has not paid enough attention to what his administration is doing and that the administration has not been competently running the government.
Similarly, Gallup’s presidential tracking poll found last week that Obama’s approval rating had dipped to 39 percent, a two-year low in its polling. It has since increased to 40 percent.
A Pew poll last week found his approval rating at 41 percent. Both previous surveys polled national adults.
The surveys are reporting lower numbers as Obama deals with the botched rollout of his healthcare law and addresses questions about millions of people on the individual insurance market losing their coverage.
"Any Democrat with an 11-point approval deficit among women is in trouble. And any elected official with an 8-point trust deficit is in serious trouble," said Tim Malloy, Quinnipiac's assistant director of polling.
Malloy noted that Obama’s approval rating is similar to that of President George W. Bush during the same period of his presidency.
Voters are split on whether Obama knowingly deceived the public when he asserted numerous times that Americans could keep their health insurance if they liked it under ObamaCare.
Last week, he apologized that people were losing coverage because of new rules included in ObamaCare and said he tasked his administration to find a solution.
Nearly three-quarters of the public believe the administration should extend the open enrollment period to buy coverage. As glitches have plagued ObamaCare.gov, some Democrats have also called for a delay.
Voters continue to oppose the law, 55 percent to 39 percent. And 43 percent of people believe their healthcare coverage will get worse next year because of ObamaCare.
The Quinnipiac poll surveyed 2,545 registered voters and contains a 1.9-point margin of error.