There is no life on Mars as we know so far. But for many years there was a lot belief that some sort of a life could be found on this planet.
There were a lot of reasons for this belief. One was that it was found that there seemed to be seasonal changes on the surface of the Mars. The life there, or if it is present, it is on some other form, which we have not been able to see.
Below Mars info from Wikipedia (Read More):-
Mars is the fourth planet from the Sun in the Solar System. The planet is named after Mars, the Roman god of war. It is also referred to as the "Red Planet" because of its reddish appearance, due to iron oxide prevalent on its surface.
Mars is a terrestrial planet with a thin atmosphere, having surface features reminiscent both of the impact craters of the Moon and the volcanoes, valleys, deserts and polar ice caps of Earth. It is the site of Olympus Mons, the highest known mountain in the Solar System, and of Valles Marineris, the largest canyon. Furthermore, in June 2008 three articles published in Nature presented evidence of an enormous impact crater in Mars's northern hemisphere, 10,600 km long by 8,500 km wide, or roughly four times larger than the largest impact crater yet discovered, the South Pole-Aitken basin.[6][7] In addition to its geographical features, Mars’ rotational period and seasonal cycles are likewise similar to those of Earth.
http://en.wikipedia.org/wiki/Mars
