The woman, a sub-inspector in Coimbatore, has alleged that she was in a live-in relationship with the magistrate following his promise to marry her.
She claims the judicial officer refused to marry her and had recently married another woman.
A court in Tirupur district court has remanded the magistrate for two weeks.
The incident comes a week after the controversial order by the Madras High Court which said that pre-marital sex is equivalent to marriage.
The High Court gave its judgement during an alimony hearing. The mother of two from Coimbatore was left by the man, who fathered her children. A court in Coimbatore had directed the man to pay maintenance for the children. However, the woman was denied alimony as she did not have valid documents of a marriage.