Harvard professor Latanya Sweeney said names typically associated with black people were more likely to produce ads related to criminal activity. In her paper, Prof Sweeney suggested that Google searches may expose "racial bias in society".
Google has said it "does not conduct any racial profiling".
In a statement to the BBC, the company said: "We also have an ‘anti’ and violence policy which states that we will not allow ads that advocate against an organisation, person or group of people." When placing ads with Google, companies are able to specify which keywords they would like to target.
"It is up to individual advertisers to decide which keywords they want to choose to trigger their ads," the search giant said. The study analysed the type of advertisements that appeared on Google when certain names were searched for.
It looked at Google.com’s core search engine, as well as the search function of Reuters.com – which also displays Google’s advertising.
Prof Sweeney’s investigation suggests that names linked with black people – as defined by a previous study into racial discrimination in the workplace – were 25% more likely to have results that prompted the searcher to click on a link to search criminal record history.