The Serbian, who occasionally struggled for momentum in her service games as her ball toss caused her problems, was never able to keep pace with world No. 11 Pliskova - just a week after losing to Britain's Naomi Broady - as her difficult preparations for the Australian Open continued.
"It was a solid win for me today," Pliskova said afterwards. "She is always tough to play. I'm happy to have more matches."
Nadal calls on Spain's athletes to raise 11m euros to fight coronavirus
Another former world No. 1, Jelena Jankovic, at least avoided Ivanovic's fate - beating Coco Vandeweghe 6-3 6-4 to bounce back after her surprise first round exit in Brisbane a week earlier.
Sixth seed Timea Bacsinszky joined Ivanovic in making an early exit, as she was beaten 1-6 6-1 6-3 by Anna Karolina Schmiedlova despite making a blistering start.
Elsewhere in Sydney, previous champion Tsvetana Pironkova beat Lesia Tsurenko 7-6 6-2, while Svetlana Kuznetsova was even less troubled as she clinched a 6-2 6-0 win over Tammi Patterson.
In the all-French tie between Caroline Garcia and Kristina Mladenovic, it was the former who triumphed as she edged an opening set tiebreak on the way to a 7-6(4) 6-4 victory.
The tournament in Sydney has got off to a rocky start, with both Agnieszka Radwanska and Petra Kvitova withdrawing due to injury.
Former tennis star Ivanovic helps buy 35 ventilators amid coronavirus crisis
Australian Open 2017 order of play, TV details, Day 13: Williams sister take centre stage once more