The duo won their respective Asia Pacific Wildcard Play-offs on Sunday to book their places in the Melbourne field.
Third seed Di eased to victory in Sunday's final in Shenzhen, beating his compatriot Ze Zhang 6-0 6-3.
The world number 205 also won the play-off event last year but then duly lost in the first round of the Australian Open.
The women's wild card went to 19-year-old Hao, who had come through qualifying to reach the main play-off draw.
Ranked a lowly 466th in the world, she saw off Risa Ozaki 6-3 6-3 in the final - her sixth match of the week - to ensure she will make her Grand Slam debut in the New Year.
The Australian Open gets under way on January 13.