Of the four, Ajit Das (18) and his grandfather Mahendra Das(58) died at Gabgaon village under Chandipur police station while Basanti Singh (12) died at Ganeswarpur under Remuna block.
Jaleswar police said one Jogeswar Jena in Mahisamunda village under Jaleswar Block also died in lightning strike.
The bodies have been sent for post-mortem.