Both teams finished with 10 players as Lyon stayed on track for a fifth straight European title.
In France, PSG have been repeated runners-up as Lyon have won 14 straight league titles. PSG have reached two Champions League finals and lost both.
“Today, once again, we are the losers, but we have reasons to be proud and carry on,” said PSG defender Irene Parades.
The two teams drew 0-0 after extra time on August 9 in the French Cup final, before Lyon won in a shootout.
For 65 minutes on Wednesday, the semi-final followed a similar pattern with neither team daring enough to threaten consistently. The momentum changed in the 65th minute.
PSG midfielder Grace Geyoro fouled English star Lucy Bronze to collect a second yellow card.
Amel Majri curled the free kick into the goalmouth and France team-mate Renard leapt high above the defence and drove a header past goalkeeper Christiane Endler.
It was the 1.87m-tall Renard’s 19th appearance in a Champions League semi-final, three more than anyone else.
Ten minutes later, English striker Nikita Parris, chasing an over-hit pass, ran into Endler and incurred a second yellow.
Back at even strength, PSG continued to struggle to create dangerous chances and Lyon held out.
On Sunday in San Sebastian they will face Wolfsburg for a third time in the final.
The Germans won in 2013, but Lyon triumphed in 2016 and 2018.
“It will be very difficult because all the teams are very close and we’re suffering a lot from injuries this year,” said Lyon president Jean-Michel Aulas.
“But let’s already savour this victory in the semi-finals.”
Two-time former winners Wolfsburg sealed a place in the final with a 1-0 victory over last year’s runners-up Barcelona in Spain on Tuesday.
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