Solar Impulse, whose wingspan is the same as an Airbus A340, flew 26 hours and 9 minutes, powered only by solar energy stored during the day.
After more than a day in the air powered by the sun, the Solar Impulse touches down in Switzerland.
The plane's 26-hour flight successfully demonstrated its ability to fly at night, using energy stored up during the day in its 12,000 solar cells.
Flying without traditional fuels, the glider-like aircraft reached an altitude of more than 8,500 metres above sea level.
Pilot Andre Borschberg says the test flight surpassed expectations.
"We almost thought to make it longer but we said no, we demonstrated what we wanted to demonstrate so they made me come back, so here I am but it was gorgeous."
The plane, constructed primarily from carbon fibre, has a 64 metre wingspan and weighs about the same as a mid-sized car.
This historic flight - which organizers say was the highest and longest in the history of solar aviation - comes after six years of development. The Solar Impulse has a budget of over 95 million dollars - most of which comes from corporate sponsors.
A second prototype will soon go into a production and the plan is to fly that across the Atlantic before preparing for round the world flight in 2012.
Matt Cowan, Reuters.