Police have charged a 29-year-old man with indecently assaulting the 23-year-old actress outside a party for cast members at a Sydney hotel on Thursday night.
She was allegedly groped on the chest by a man who had asked her to pose for a photograph, The Sydney Morning Herald newspaper reported.
The actress who plays big-eyed teenager Haley Dunphy immediately alerted private security guards, who called police to the scene.
The actress was shaken by the incident, and left early from the event sponsored by Qantas Airways, the newspaper said.
"Sorry to all the fans outside the #qantas event that I didn't get to say hi to but I had to leave due to an inappropriate touch of a fan," she wrote on Twitter.
Her actor boyfriend who accompanied her to Australia, Matt Prokop, tweeted: "To the (expletive) who assaulted Sarah tonight I hope to God you don't see next week."
Ten Network, which broadcasts the ABC series in Australia and boasts exclusive access to the Australian filming, showed video of a relaxed Hyland acting a scene at Sydney's Bondi Beach on Friday with other cast members.
"Sarah's fine," executive producer Steven Levitan told Ten on the beach.
"Of course, as your can imagine, it's gotten completely blown out of proportion. She's fine. It was handled very, very quickly," he added.
The cast arrived in Sydney this week to shoot an Australian episode. Hyland said they had been enjoying themselves.
"It's a lot of fun to be here, especially with this cast and our crew because we're also so tight-knit," she told Ten on Thursday before she was assaulted.
Her alleged assailant was charged
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