The 31-year-old Peng made light work of the Japanese in just under 90 minutes to add to the maiden WTA singles crown she won last year, also on home soil, in Tianjin.
Peng, with a world ranking of 32 and the tournament's second seed, was never really in trouble on the outdoor hard courts at Nanchang in southeast China.
Hibino, 92 in the world, drove a two-handed backhand into the net from the baseline to gift the home favourite the match.
Peng, nearly a decade older than her opponent, raised both hands to the evening skies in celebration as she made the perfect start to the summer hard-court season.
The tournament, where sweltering temperatures troubled players throughout the week, had opened up nicely for Peng.
Fellow Chinese and top seed Zhang Shuai and European stars Jelena Jankovic and Kristyna Pliskova all tumbled out early to leave Peng as the sole remaining seed in the semi-finals.