The designs are selected from a contest which was launched by the Vietnam General Confederation of Labour (VGCL) more than two months ago.
The contest attracted the participation of 21 collectives and individuals from across the country.
Dang Ngoc Tung, VGCL President, said the contest was meant to find the best design for a memorial which must fulfill requirements of feasibility, sustainability, aesthetics and historical education values.
Based on public opinions, the organising board will select the best design, and construction on the site will begin in January next year after being approved by competent agencies, he said.
The exhibition will last until December 17.