The elderly man allegedly approached the teenager around 11am yesterday and proceeded to stroke her hair and attempt to kiss her, The Daily Telegraph reports.
The girl left the shop she was in and went to a nearby toilet. Police say the man followed her and proceeded to sexually assault her.
Alerting security guards at the earliest opportunity, who quickly got police involved, the man was arrested the man at his home in Waitara shortly after, NSW Police report.
He was being refused bail and charged with aggravated indecent assault and two counts of aggravated sexual assault of a victim under the age of 16 years.
He is due to front Hornsby Court today.