Seriously, Dude, Ashton Kutcher of “That ’70s Show” is more than just a pretty face.

The 6-foot-3 Iowa corn-fed cutie, who broke into showbiz modeling Calvin Klein jeans, was a biochemical engineering major in college!

That’s a far cry from lamebrained Michael Kelso he plays on the hit FOX-TV show, or pot-addled Jesse Montgomery III in “Dude, Where’s My Car?”

In fact, Ashton, 24 — who starts filming the follow-up “Seriously Dude, Where’s My Car?” this summer — was a straight A student in high school before going to the University of Iowa to study biochemistry.

But biochemistry couldn’t compete with the allure of a showbiz career.

In 1997 Ashton won the Fresh Faces of Iowa modeling contest and then, after just one year on the runways of New York and Milan, he landed “That ’70s Show.”

Now he’s one of the most sought-after young bachelors in TinselTown.

He had a long-term relationship with fellow model and actress January Jones, who he met in 1997 on an Abercrombie & Fitch photo shoot.

More recently, say insiders, he hit it off with actress Krista Allen, who was dating both George Clooney and Matthew Perry.

For now, however, Ashton appears content to share his Hollywood Hills home with only his two prize pets — a golden retriever named Mr. Bojangles and a tomcat, Mr. Fido.