The 5-foot-11 Landstrom, who spent the last three seasons at Linkopings FC, made two appearances for Sweden at Euro '09.
"Jessica has a great physical presence on the field," Sky Blue FC coach Pauliina Miettinen said. "She is big and strong and will serve us well as a target player. I am confident she will fit right into our system of play."
Sky Blue FC has already signed U.S. international Carli Lloyd, Dutch international Daphne Koster and American Ashleigh Gunning in the offseason.
"Our goal in the offseason was to make our team better. I feel we accomplished that with the addition of Carli Lloyd to the midfield and Daphne Koster and Ashleigh Gunning to the back line," Sky Blue FC general manager Gerry Marrone said. "However, our strongest need was up front -- to find a proven goal scorer. Jessica is the prototypical target: she can play with her back to the goal, is commanding in the air and a big physical presence. This season in Sweden, she was one of the leading goal scorers, and more importantly, scored some big goals in big games."