Ivanka Trump recently assumed an official role in her father's administration. She moved into a West Wing office and obtained a security clearance in late March.
About 53% of respondents said the first daughter playing a significant role in the White House is not appropriate, compared with 36% who said it was appropriate and 10% who did not have an opinion.
Kushner, her husband, also has a broad portfolio within the West Wing, where he has an influential purview over a range of foreign and domestic policy issues. He is heading up the Office of American Innovation, a new White House office aimed at reforming the federal government through private-sector solutions.
About 53% said his role was not appropriate, compared to 32% of respondents who said it was appropriate and 15% who did not know.
But when it comes to overall popularity, fewer have unfavorable opinions Trump's family than the President himself.
About 56% of those surveyed had an unfavorable opinion of Trump, compared to 39% who had a favorable opinion of him. That compares with 31% with unfavorable opinions of Ivanka Trump and 36% with favorable opinions, and Kushner, with 32% unfavorable to 15% favorable. About half of respondents had not heard enough about Kushner to have an opinion.
First lady Melania Trump has a 34% favorable rating versus 24% unfavorable and 35% who have yet to form an opinion.
"When it comes to President Trump's immediate family, Ivanka and the first lady get so-so marks," said Tim Malloy, assistant director of the Quinnipiac University poll.
Melania Trump's biggest demographic of supporters is aged 65 and older; she performed the worst among the youngest group, polled at just 25% favorable for those between the ages of 18-34. The margin of error for this age group was plus or minus 8.5% points.
Divided between gender, she's also more popular with men, 37% of whom view her favorably, versus 32% of women, with margins of error of plus or minus 4.1% points and 4.5% points, respectively.
Divided between party lines, the numbers scale toward partisan expectations. Seventy-one percent of Republicans have a favorable opinion of the first lady, while just 9% of Democrats like her.
Ivanka Trump also gets her lowest marks from the millennial age bracket, similarly to the first lady. Just 24% of respondents age 18-34 have a favorable opinion of the first daughter, compared to 36% unfavorable. Older respondents had net positive opinions about her.
She also got slightly higher marks from men -- 38% have a favorable opinion, compared with 35% of women.
The poll surveyed 1,062 voters nationwide between April 12-18 and has a margin of error of plus or minus 3% points. The demographic or partisan breakdowns have larger margins of error.