Ashma Khatun tried to kill herself due to marital discord with her husband Bashir Ibrahim Sheikh, they said.
Ashma was living at her parent's house in the town since last seven months after falling out with her husband, said R R Jadhav, inspector of Patan police station.
"This morning she went to a spot located some two kilometres on the outskirts of town near Hiran river and threw her son Ashfaq (7) before jumping into the river along with her two other sons, Shabbir (4) and Inayat (2)," Jadhav said.
Their bodies were later fished out by the locals.
"A case will be registered against the woman," Jadhav said, adding a probe was underway.