Three members of a family, including a minor, drowned in the backwaters of a dam near Talegaon in the district during a picnic on Sunday afternoon, police said.
Three other members of the family were rescued by a team of the National Disaster Response Force (NDRF), which was holding a training session nearby.
The victims were identified as Prashil Adhav, 7, Anil Kolse, 58, and Pritesh Agale, 32.
Talegaon MIDC police said one Gaikwad family from Khed along with their relatives from Mumbai had gone for a picnic near the backwaters of Jadhavwadi dam near Talegaon.
"Kolse fell into the water while he walking near the dam. Some of the family members tried to save him, but fell into water," an officer said.
"Someone alerted the NDRF team, which was conducting a training nearby. While three were rescued, three others drowned. They were shifted to a hospital, which declared them brought dead," he said.
A case of accidental death was registered, police said.