Men are shelling out increasingly big bucks for their shoes — and Saks Fifth Avenue is gearing up to chase them.

The luxury retailer on Monday revealed plans to open an 8,000-square-foot shoe department at its Fifth Avenue flagship on Wednesday — hawking everything from $65 Pumas to an $11,000 pair of Pierre Corthay alligator loafers.

The new, sixth-floor emporium will be 60% larger than its predecessor and will boast at least 2,000 different pairs from more than 60 luxury brands, said Saks president Marc Metrick.

The bold bet comes as men’s footwear has become the fastest-growing business at Saks, fueled in particular by surging demand for blingy sneakers, Metrick said.

“Fashion is incredibly important to men,” Metrick told The Post. “And footwear is their gateway drug.”

Sales of men’s shoes at Saks have grown by more than 50% over the past three years. The spike has been driven by fashion sneakers like the $695 Superbowl suede skate sneakers from Fear of God, the $650 Givenchy Urban Street NYC Low Tops and the $895 Balenciaga Triple S trainers.

Owned by Canada-based Hudson’s Bay, Saks is trying to replicate the success of its massive women’s shoe department, a 30,000-square-foot mecca that opened a dozen years ago and which took its own ZIP code, 10022-SHOE.

“The women’s footwear department became the headquarters of women’s shoes,” Metrick said. But “men’s apparel was an afterthought for a long time in department stores.”

Industrywide, sport leisure shoes accounted for 90% of the 5% growth in men’s footwear year-to-date through May, according to NPD Group/Consumer Tracking Service.

“The male consumer today cares more about his appearance than in previous years and the statement piece is footwear,” NPD analyst Marshal Cohen told The Post.

At Saks, that has meant rabid demand for $320 black Gucci Pursuit slides that are decorated with tigers, $690 chunky leather holographic sneakers by Alexander McQueen and $790 black and canary yellow “sock sneakers” by Fendi.

As part of a $250 million multi-year renovation, Saks has been adding other destinations to its flagship, including an acclaimed new eatery, L’Avenue, which opened in February; an experiential beauty department, which was moved to the second floor last year; and a larger handbag selection, now on its ground floor.

Man bags, which have long drawn hesitation among some members of the male crowd, are soon “going to be a thing,” according to Metrick.