The narcotics consignment was being brought to India by two Nepali nationals, identified as Chhavikant Mahto and Jitendra Das, on a motorbike.
SSB Patna Frontier IG Aditya Misra said, "This is a major seizure done by our 27 battalion. Our boys are investigating the case further."
SSB officials said the two drug conduits were challenged and intercepted near border pillar number 427/ 13 near Panchrauta village in West Champaran district, around 200 kilometres from here.
Nepali charas has a good demand in the international market and fetches over Rs 10 lakh per kilogram.
SSB sources said during interrogation, the arrested duo said they had been given the consignment by one Chaudhary in Nepal.
Both the Nepali nationals have been handed over to the Bhanga police station for further action.