Police said officers observed the spectators allegedly disrespecting the anthem while it was playing.
“They turned their backs to the field and did not stand while the national anthem was playing,” the force said.
The trio, aged 18 to 31, were arrested on suspicion of insulting the national anthem after further investigation.
The case was handed over to the Wan Chai district crime squad.
Police said the three had been released on bail, but would be required to report to the force again in early July.
In July last year, the first person to stand trial under Hong Kong’s National Anthem Ordinance was sentenced to three months in prison.
Cheng Wing-chun was found guilty after posting an edited clip of fencer Cheung Ka-long celebrating his Tokyo Olympics victory, in which the national anthem was replaced with “Glory to Hong Kong” – a song linked to anti-government protests.
Controversies related to the national anthem, “March of the Volunteers”, at football games have also been widely reported.
In 2022, fans booed the song ahead of a match between Hong Kong and Myanmar, and while police were seen filming the audience, no arrests were made on that occasion.
Such incidents were regular occurrences at football events for years before the ordinance was enacted in 2020. The Hong Kong Football Association had been warned or fined multiple times by higher sporting bodies over the behaviour of city fans.
Anyone convicted of intentionally insulting the anthem can face up to three years in jail and a maximum fine of HK$50,000 (US$6,370) under the ordinance.