Three people died and dozens were injured when Asiana Flight 214 crashed on 6 July 2012.
The Department of Transportation said Asiana took up to five days to notify the families of all 291 passengers.
Regulators also said the carrier lacked translators and trained crash staff.
It is the first time an airline has ever been fined by regulators for failing to obey a 1997 US law that mandates prompt assistance to the families of crash victims.
"In the very rare event of a crash, airlines have a responsibility to provide their full support to help passengers and their families by following all the elements of their family assistance plans," said US Transportation Secretary Anthony Foxx in a statement.
"The last thing families and passengers should have to worry about at such a stressful time is how to get information from their carrier."
Officials said the Korea-based airline took five days to send all necessary personnel to San Francisco to deal with the emergency.
They also said that for at least 24 hours after the crash, Asiana failed to provide a number families could call to find out more information about the incident.
When family members eventually were able to call, they were initially routed to a reservations line rather than a crisis hotline.
The Boeing 777 crashed at San Francisco's international airport after the plane came in too low and hit a sea wall.
The plane's pilot later said he was worried he hadn't had enough training to properly land the plane without the assistance of the instrument landing system, which was out of service for repairs at the time.
US regulators have fined Asiana Airlines $500,000 (£300,000) for failing to help victims of a flight crash last year at San Francisco's airport.