That's significantly higher than the 33% of Hispanic parents and 26% of white parents who expressed vaccine hesitancy, the findings showed.
"As vaccines are becoming available to younger children, and with continued spikes in COVID-19 cases, it is of the utmost importance that we are able to widely distribute the vaccine," said study co-author Dr. Jennifer Kusma, a pediatrician at Lurie Children's Hospital of Chicago.
"We especially need to reach the more vulnerable and hesitant populations to help reduce the substantial health inequities we have seen during this pandemic," she said in a hospital news release.
For the study, Kusma and her colleagues surveyed parents of children under 18 years of age living in Chicago and the surrounding suburbs. Responses from more than 1,400 participants were analyzed.
Overall, the study found, 33% of parents were hesitant about the COVID-19 vaccine for their children.
The survey was conducted in June 2020, before the Pfizer COVID-19 vaccine was approved for use in 12- to 17-year-olds.
Pfizer-BioNTech submitted data to the U.S. Food and Drug Administration on Sept. 28 that they said showed their vaccine is safe and effective for 5- to 11-year-olds, as well.
But persuading some parents to have their kids vaccinated may be a tough sell, the survey suggests.
Besides Black parents, parents with public health insurance were also more reluctant to have their kids get COVID-19 shots (41%) than parents of children with private insurance (26%), the researchers found.
"We found that parents who turn to family, internet and health care providers for COVID-19 information were less likely to report vaccine hesitancy for their child," Kusma added.
The survey findings were recently published online in the journal BMC Public Health.
The U.S. Centers for Disease Control and Prevention has more about the safety of the Pfizer-BioNTech COVID vaccine.