Pawan Yadav, 28, was arrested late Thursday night under section 304b (causing dowry death) of the Indian Penal Code.
"A case of dowry death has been registered against her in-laws," a police officer said.
Satyam, 26, of west Delhi's Nangloi area, was found hanging inside her home around 8 a.m. Thursday. The body of her one-and-a-half-year-old daughter was lying on the bed.
Satyam, a native of Bulandshahr in Uttar Pradesh, had moved to Delhi in 2010 after her marriage to Pawan Yadav, a teacher in a municipal corporation school.
She had a masters and B.Ed degree and was a councillor from ward number 43 in Nangloi (East).
Satyam's family members registered a complaint against her in-laws alleging that she was murdered because of dowry.
"Satyam's in-laws were demanding Rs.10 lakh (as dowry). We went to Delhi to bring her back to Bulandshahr. They refused to let her come and said they will not leave her until their demands were fulfilled," said Satyam's elder brother Nishant Yadav.
Pawan Yadav refuted the dowry allegations and told investigators that his wife was upset over a family issue.
Satyam's family members refused to accept that she had committed suicide.