The deceased are identified as Hiru Bapari, 40, of Munshidangi village in Faridpur Sadar Upazila, Bashar Molla, 35, of Barnichar village in Boalmari and Nur Nabi Milon, 40, of Syedpur village in Sonagazi Upazila.
The lightning struck the areas between 2pm and 6 in the evening on Friday.
All the victims were at work when they were hit by the lightning. Hiru was a fishmonger while Bashar and Nur Nabi were farmers.