Third-seeded de Minaur dispatched American Bradley Klahn 6-4, 6-4, after only 67 minutes, dropping only two points on his first serve without facing a break point in the match.
The world number 34 booked a first-ever ATP matchup Friday against 106th-rated compatriot Tomic, who eliminated Aussie Matthew Ebden 6-4, 7-6 (7/3).
Tomic seeks his fifth ATP title after wins last year at Chengdu, 2014 and 2015 in Colombia Open and 2013 in Sydney.
De Minaur seeks a second title after hoisting his first in January at Sydney after losing there in the 2018 final.
The winner of the Aussie showdown will face either Britain's Daniel Evans or American Reilly Opelka in the semi-finals.
Later second-round matches Thursday send US second seed Taylor Fritz against countryman Kevin King and French eighth seed Ugo Humbert against Serbia's Miomir Kecmanovic.