He had given his daughter "massages" on the pretext of following doctor's advice.
The girl was diagnosed with scoliosis - a spinal disorder - when she was in primary school.
But the father, 47, who cannot be named to protect his daughter's identity, took advantage of her in 2007 by molesting her during one of the massage sessions.
Yesterday, the man pleaded guilty to outraging his daughter's modesty by using "criminal force". He will be sentenced later.
The girl, who was about 11 years old then, followed him to the master bedroom of the flat in central Singapore.
Court documents showed that the man claimed he had wanted to massage her spine.
He locked the door although there was nobody else at home at the time, and told the girl to remove her shirt.
She was made to lie face down on the bed. While massaging her, he lifted her bra and told her to sit up. He then molested her.
He continued to molest her after telling her to remove her shorts and panties. The girl, who was traumatised, decided to keep silent.
The incident came to light three years later, after the girl confided in her secondary school teacher who then reported it to the school authorities.
The teacher had noticed that the girl "was exhibiting suicidal tendencies and self-injuring", court papers revealed. The girl finally made a police report in November 2010.
The man can be jailed up to two years, fined or caned.
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