Gustavsson was discovered at an IKEA when she was 12 years old. She began modeling locally in 2008, and in the same year she moved to Japan to pursue modelling. She opened the Valentino Haute Couture fall 2012 show in Paris. Since then, she has walked shows for Shiatzy Chen, Louis Vuitton, Chanel, Lanvin, Carolina Herrera, Fendi, Christian Dior, Jil Sander, Alexander McQueen, Anna Sui, Marc Jacobs, Michael Kors, Calvin Klein, Oscar de la Renta, Emilio Pucci, Celine, Hermès, Jean Paul Gaultier, Dolce & Gabbana, Givenchy, Yves Saint Laurent, Ralph Lauren, Blumarine, and Versace. She also walked in the Victoria's Secret Fashion Show 2012. Gustavsson is also the new face of Maybelline, she was going to work for them in ads and commercials in the late 2013. She was the fourth most requested model of the spring 2010 season, behind Kasia Struss, Liu Wen, and Constance Jablonski.
Gustavsson has been in the magazines Elle, W, Numéro, American, Italian, French, British, German and Japanese Vogue, L'Officiel, Crash, and others. In March 2010, she appeared on the cover of the German Vogue. She has appeared in advertising campaigns for Marc Jacobs, Jill Stuart, Anna Sui, H&M, Max Mara, Tiger of Sweden and Prada. Gustavsson won Elle Sweden's Model of the Year award in 2011.
