A 26-year-old biology teacher from Hwa Chong Institution was on board the missing AirAsia flight QZ8501.
Ms Florentina Maria Widodo, from Indonesia, is affectionately known to family and friends as Tina.
She teaches A-level biology at the school. Her name is listed as No. 135 on the passenger list issued by the airline on Sunday.
Her Singaporean boyfriend, Andy Paul Chen, was at Changi Airport yesterday afternoon to travel to Surabaya, Indonesia.
"She is my girlfriend. I'm going there now to meet her family members," he told reporters in Mandarin.
He was accompanied by his parents, and seemed to be in shock.
Ms Widodo and Mr Chen had both studied at the National University of Singapore, and were members of the university's guitar ensemble.
Ms Widodo reportedly graduated from the National Institute of Education last year.
Mr Chen took to Facebook on Sunday to inform friends and family members that Ms Widodo was among the passengers on board the aircraft.
Her father, who is named as FY Widodo on Facebook, posted a photo of himself and his daughter on the social-networking site.
Get MyPaper for more stories.