Kim K Struggles in Skintight Dress at Fashion Week in Milan

Kim Kardashian made an incredible entrance Saturday at Milan Fashion Week ... but she had to choose between looking awesome and simple tasks, like walking!

Kim tried hoofing it up a flight of stairs, and it was a Herculean effort in her beyond-skintight getup.

What made it more challenging ... all eyes were on her, and there were LOTS of people staring .. for obvious reasons -- she looked incredible.

She was there with fashion photog Mert Alas ... who has become a leader in digital manipulation.

No manipulation here ... it's the real deal, and clearly a real struggle.