The Friday report says Tehran police arrested 140 of the young partygoers in a garden on the outskirts of Tehran and 90 in the city's uptown while dancing and drinking alcohol Thursday night.
Drinking alcohol and mixed parties of unrelated men and women are illegal and considered a sin under Islamic law in Iran.
The report said some participants posted an invitation to others to join on Instagram and police arrested them.
ISNA also said some alcoholic beverages and psychotropic drugs were confiscated.