Pistorius ran 21.30, shaving more than half a second off the previous record set by Brazilian Alan Fonteles Cardoso Oliveira in an earlier heat.
The 25-year-old, who is dubbed the 'Blade Runner', is defending the 100m, 200m and 400m Olympic titles he won in Beijing four years ago.
Pistorius, who wears carbon fibre prosthetic blades after he was born without a fibula in both legs, became the first double amputee to run in the Olympics, where he made the 400 metres semi-finals.
"I'm so happy to be back here This crowd is as awesome as they were a couple of weeks ago. I'm happy with the time and tomorrow is the big race and I am looking forward to that," he told Channel 4.
"To be out here representing our country in such an amazing stadium is so amazing."
Pistorius, who was roared around the Olympic stadium by a passionate London crowd, is now the hot favourite to clinch 200m gold in Sunday's final.
His scorching time has given him confidence that he might be able to complete the clean sweep as he did in China four years ago, although he admits the 100m is where he will face his stiffest test.
He ran his first 100m in 16 months in Warsaw recently and put in a good performance, but he knows his competitors are now more finely tuned than ever.
"A world record tonight so we will see what happens, but the 100m is not my event," he added.
Returning to the Olympic stadium, Pistorius said he was impressed with how London had embraced the Paralympics.
"I have been here so many times and have never seen things that I have seen here lately.
"You get on the subway and people hold the door and help each other out.
"It has really transformed the city and the perception of a lot of people. I think the things that sport can do for a country are absolutely mind blowing."