The £5m push, created jointly by Hyundai's in-house agency Innocean and US agency David & Goliath, will run for 10 weeks across TV, cinema, and print, including special promotions through Metro and i.
The ads target younger, female drivers, and feature a pet cat carrying out unlikely feats, such as swinging from trees and scaring a dog.
The campaign will carry the tagline "Small yet mighty," and emphasise the deceptive qualities of the Picanto, despite its small size.
The campaign will also push Kia's seven-year warranty offer, as well as driving prospective car buyers to an interactive "iBrochure" for Picanto.
Simon Hetherington, the outgoing Kia UK marketing director who is moving to the new role of dealer development director, said: "We've embraced digital technology in all aspects of the launch, including developing a new iBrochure – a modern alternative to the traditional car brochure."
Kia recently called a review of its £60m pan-European ad account. The successful agency will be responsible for creating all marketing activity for the launches, including TV, digital and in-dealership work.