Images of the car had already leaked out on social media after the team conducted a filming day at Barcelona on Saturday.
The new Haas featured an adjusted livery with a greater degree of grey, as well as the 'shark fin' on the engine cover that most 2017 F1 designs so far have featured.
"The pedal box is the same, but all the rest is very different from last year's car," said Haas team principal Gunther Steiner.
"You always try to make a faster car, which is normally a lighter car.
"Now we can put on more ballast and get better weight distribution. The aero is completely new, as are the tires, so we needed to have some built-in adjustability.
"Aesthetically, the car has a more aggressive look. It's lighter and more aerodynamically efficient.
"Everything we learned from our first car has been applied to our new car."
Haas made a spectacular start to life in F1 when Romain Grosjean took top-six finishes in the team's first two grands prix.
It could not maintain that momentum, but its later slump was partly because Haas decided to switch resources towards preparing for the 2017 rules particularly early and carried out little in-season development with the '16 car.
Grosjean stays on for 2017, with Kevin Magnussen moving from Renault to replace Esteban Gutierrez alongside him.