Timofei Kalachev scored twice for the hosts with Maksim Bordachev and Leonid Kovel also getting on the scoresheet.
The result was vindication for home coach Bernd Stange's decision to omit several big-name players, including Stuttgart star Alexander Hleb, his brother Vyacheslav and BATE Borisov midfielder Igor Stasevich, in an attempt to look to the future.
Kalachev was the outstanding performer, making his first significant contribution after 23 minutes.
His pass played in Bordachev and his shot beat Kazakhstan goalkeeper Alexandr Mokin.
The hosts' lead was doubled in the 69th minute when Kalachev picked up the ball and lashed in a wonderful 35-yard effort.
Kazakhstan heads dropped and it was no surprise that they conceded twice more in the closing stages.
Kovel, a 73rd-minute replacement for Vitaly Kutuzov, made it 3-0 with four minutes remaining.
He found himself clear on goal and showed commendable composure to clip the ball past Mokin.
Kalachev completed a comprehensive win from close range in injury-time.
The heavy defeat extended a disappointing qualifying campaign for Kazakhstan, whose only points have come against group minnows Andorra.
Belarus have fared better but are still well adrift of pool heavyweights England, Croatia and Ukraine and not in contention for a place in South Africa next summer.