They joined Serena Williams and defending champion Naomi Osaka who also bowed out in the third round the day before.
Pliskova went in straight sets to Russian, Anastasia Pavlyuchenkova, 7-6 (7-4), 7-6 (7-3), with the Czech player rueing not performing better in the tie-breaks, reports Xinhua news agency.
"I was kind of close both sets well, a lot close, and I think I was still able to somehow win this match if I at least played a little bit better. But unfortunately I didn't," Pliskova said.
Meanwhile fifth seed Svitolina went down to Spain's Garbine Muguruza, 6-1, 6-2, while sixth seeded Bencic was sent packing by Estonian Anett Kontaveit, 6-0, 6-1.
Bencic explained that upsets were a part of the sport and a consequence of not playing in full form.
"It's the same at every Grand Slam, there are upsets, and I think it's normal, because it's tennis, and tennis is very unpredictable," she said.
Bucking the trend was Romanian World ranked No. 3, Simona Halep, who won her tie against Kazakh Yulia Putintseva, 6-1, 6-4, to progress to the final 16.
In the men's draw, Russia's Karen Khachanov lost in an epic match tie-break to Aussie favourite Nick Kyrgios, 6-2, 7-6 (7-5) 6-7 (6-8), 6-7 (7-9) 7-6 (10-8).
Meanwhile, Rafael Nadal stepped up a gear to beat fellow countryman Pablo Carreno Busta 6-1, 6-2, 6-4.
The World No. 1 said after the match that he felt he had found better form, describing the match as an important step towards the second half of the tournament.
"It was my best match of the tournament so far, without a doubt. Big difference between today and the previous days," Nadal said.
"I have been serving well, starting to create damage with the forehand. Hitting serve on one shot," he added.
Also moving through on Day 5 of competition was Austrian Dominic Thiem who beat American Taylor Fritz 6-2, 6-4, 6-7, (5-7), 6-4, while French player Gael Monfils defeated Latvian Ernests Gulbis 7-6 (7-2), 6-4, 6-3.
Monfils and Thiem will play each other in the next round on Monday, while Nadal will face Kyrgios.
( With inputs from IANS )