"People meet there, pass by each other, and if they like one another they can start a relationship," Filip Drapal, spokesman for the Ropid company involved in the project, told AFP.
The special cars are part of a drive to make public transport more popular.
"We are planning a campaign to show people things they can do on public transport," Drapal said.
So along with reading or studying, bored commuters will soon be able to flirt or pick up a date
The Prague "Love Train", which will promote a laissez-faire approach rather than strict speed-dating rules, is due to launch at the end of the year.
Drapal said the company was now deciding which of a train's five cars would be most suitable, the number of trains to include and what kind of signage to display.
"We're planning a poll of passengers. The carriage will be marked, and there will be information on the platform and inside the carriage, in foreign languages too."
Passengers take some 1.5 million rides a day on the Prague subway's three lines. The capital is home to 1.25 million people.
Drapal said no one will be forced to flirt in the special cars, but some passengers are still concerned.
"When I'm in a rush, I enter the first open door I see. I should watch out now and make sure no one starts seducing me," said Petr Voracek, quoted by the DNES daily.
"As a notorious metro catcher I'm afraid I might become the butt of gossip," added Karolina Vranova.
"What if someone sees me in the carriage and tells my boyfriend?"