Wycombe Wanderers, Oxford United and Thames Valley Police are investigating reports of homophobic comments from the away stand during Saturday's League One game at Adams Park.
The alleged comments were reported by home goalkeeper David Stockdale.
The police say the reports concerned "a very small minority" of fans.
"The vast majority of supporters at this game behaved in an exemplary manner, and were a credit to both football clubs," said Sgt Simon Gray.
"But we take reports of this nature very seriously and will work with both clubs to investigate these allegations."
Oxford say they "will wait for reports to be completed but will work with the safety team at Wycombe Wanderers."
They added: "The club will examine all of the available evidence but would like to state as clearly as possible that discrimination of any kind is not acceptable at matches, home or away, or on social media."
An 18-year-old man from Oxfordshire was arrested for an unrelated incident of invading the pitch, and received a conditional caution.