Needing to defeat the visiting side by at least four goals to squeeze through from Group D on the head-to-head tie-breaker, the east Africans scored three second-half goals to succeed in Dar-es-Salaam.
It was a multi-national triumph for 'Yanga' with Tanzanian Mudathiri Yahya, Burkinabe Stephane Aziz Ki, Zambian Kennedy Musonda and the most crucial goal came from Ivorian Joseph Gnadou because Belouizdad had began the match with having won 3-0 in Algeria last November.
Victory for Young Africans also ensured record 11-time champions Al Ahly of Egypt, who beat Medeama in Ghana on Friday, also qualified for the knockout stage. Ahead of the final round in Group D on March 1, Ahly have nine points, Young Africans eight, Belouizdad five and Medeama four.
Ahly will host Young Africans in a match to decide who tops the final standings while Belouizdad have home advantage over Medeama in a dead rubber.