The unseeded American broke serve in the fifth game of the opener and again in the ninth but the two-time Brisbane International champion regained her intensity to continue her fine start to 2019.
Pliskova won 34 points in the second set with 20 of those winners - and an early break in the deciding set continued the shift in momentum.
Madison Brengle was beaten by Pliskova but did manage to take the opening set
Image credit: Getty Images
Brengle's hopes of an upset evaporated as Pliskova fully overcame her slow start to not drop a game in the third and complete her routine victory in one hour and 38 minutes.
The result means the former world number one has reached the third round of the Australian Open for a fifth straight year.
Pliskova will face the Italian Camila Giorgi in the third round after she needed just 59 minutes to thrash Iga Swiatek 6-2 6-0 at the 1573 Arena.
Highlights: Camila Giorgi demolishes Iga Swiatek in straight sets
Meanwhile, Venus Williams survived a scare against Alize Cornet to reach the third round.
Williams, who had taken the first set 6-3, was caught out by a fired-up Cornet, who took the match to a decider, playing some excellent tennis to take the second stanza 6-4.
However, Cornet's brief flirtation with progression was abruptly ended as Williams turned on the after-burners to bagel her opponent in the deciding set and progress in emphatic fashion, 6-3, 4-6, 6-0.
The 13th seed Anastasija Sevastova will play Wang Qiang in the third round after she overcame the dangerous 18-year-old Bianca Andreescu 6-3 3-6 6-2.
Sevastova, who dropped just four games in round one against Mona Barthel, looked in supreme form in the opening set but the 109th-ranked Andreescu clawed her way back into the contest to force a decider.
But Sevastova booked her date with the 21st seed Qiang with Andreescu eventually producing 49 unforced errors as she ran out of gas.
Anastasija Sevastova overcame a second-set wobble to progress
Image credit: Getty Images
Elsewhere, Elise Mertens continued her 100 per cent record at majors against opponents outside the top 50 as she beat Margarita Gasparyan in straight sets.
The 12th seed eased past Anna Karolina Schmiedlova in straight sets on Tuesday, and despite the Russian Gasparyan fighting back following a one-sided opener, last year's semi-finalist held her nerve to complete a 6-1 7-5 victory at the 1573 Arena.
Mertens will face Madison Keys in the next round after the American won in straight sets 6-3 6-4 against Anastasia Potapova.
Headline act Serena Williams breezed into the third round with a convincing win over Eugenie Bouchard.
Serena Williams strolls into Australian Open third round
And there was also a big win for world number one Simona Halep, who overcame a tough test to beat Sofia Kenin in three sets.
27-Camila Giorgi (ITA) bt Iga Swiatek (POL) 6-2 6-0
7-Karolina Pliskova (CZE) bt Madison Brengle (USA) 4-6 6-1 6-0
21-Qiang Wang (CHN) bt Aleksandra Krunic (SRB) 6-2 6-3