An armoured train left a railway station in Artyom, about 124 miles (200km) from the border with his country on Sunday.
Russia’s minister of natural resources Alexander Kozlov and Primorye regional governor Oleg Kozhemyako were at a cermony to send him off.
A Russian military band playing both nations’ national anthems as well as the Russian patriotic march song Farewell of Slavianka.
The North korean leader was reportedly presented with five kamikaze drones and a bullet proof vest as a gift.
Governor Kozhemyako also handed him anti-thermal imaging clothes and a reconnaissance drone, Russia’s state media agency Tass reported.
Onn his first overseas trip in more than four years, the North Korean leader met with Vladimir Putin and visted military sites and technology hubs.
He pledged support for the Russian leader in what he has described as the “fight against imperialism”. The US had warned North Korea not to pledge to sell weaponry to Russia to aid its occupation of parts of Ukraine.
Meanwhile South Korean President Yoon Suk Yeol said: “Military cooperation between North Korea and Russia is illegal and unjust.”
He also said it “contravenes UN Security Council resolutions and various other international sanctions”.