The deals would be signed later this month, Sheiman said, providing no further details.
Belarusian defense plants build armored vehicles and other weapons, and its military has big arsenals of Soviet-made jets and tanks.
Sheiman also said Belarus would receive lucrative contracts for oil exploration in Venezuela.
Venezuela also has purchased some US$3 billion (EUR2.2 billion) worth of arms from Russia, including 53 military helicopters, 100,000 Kalashnikov rifles, 24 SU-30 Sukhoi fighter jets and other weapons. The United States has voiced concern about Venezuela's military spending.
On his recent trip to Belarus, Chavez called for a strategic partnership with the ex-Soviet nation, saying his Belarusian counterpart is a "brother-in-arms" and lamenting the pressure he said the United States was putting on Minsk and Caracas. The United States and other Western nations have dubbed Belarus "Europe's last dictatorship" because of authoritarian President Alexander Lukashenko's relentless crackdown on dissent and free media.