Police said Omenihu was booked at the Santa Clara County Main Jail but later posted bail and is no longer in custody, adding that the Santa Clara County District Attorney's Office will consider possible charges.
Officers responded at approximately 4:39pm local time on Monday to investigate the incident and that Omenihu was "co-operative" with officers.
"An adult female... called to report that her boyfriend, Charles Omenihu, pushed her to the ground during an argument. Officers did not observe any visible physical injuries to the survivor, she did, however, have a complaint of pain to her arm," San Jose police said in a statement.
"Based on the victim’s statement and the complaint of pain, Omenihu was arrested."
The 49ers will travel to Philadelphia to play the Eagles on Sunday in the NFC Championship.
"We are aware of the matter involving Charles Omenihu and are in the process of gathering further information," the team said in a statement.