The West Java administration has issued a circular banning students in the conservative province from celebrating Valentine's Day, saying the Western tradition was against prevailing "religious, social and cultural norms."
West Java Education Agency head Ahmad Hadadi signed the letter on the ban on Friday.
"[The administration] bans students from commemorating Valentine's Day on February 14, 2017 at school or outside school," he said.
The official argued that the ban was part of the government's efforts to build good moral character in students and prevent them from engaging in activities that contravened religious, social and cultural norms.
The circular, he said, had been sent to 27 education agencies in the province.
Local education activist Eko Purwono said the ban was useless, as it simply could not be enforced.
"If [students] buy cannabis or crystal meth, police would take action against them," he said, pointing to the fact that there is no legal ground to criminalize those celebrating Valentine's Day.
He said he wondered if the administration would actually ban students from buying chocolates on Valentine's Day.
Debates over Valentine's Day happen every year in Indonesia, home to the world's largest Muslim population.
The celebration has a strong cultural and commercial presence in the country, despite objection from conservative groups.