Why earth attracts all kind of matter? Is it because of magnetic field? I saw magnets attract only iron.?

The only one who attracts the iron in my house is the cleaner!

It is all down to mass and velocity. Forget what you think you know about attraction and magnetism, and think about the curvature of the space time fabric and the way a large mass, such as planet Earth, affects this "fabric", traveling through it at approximately 66500 m.p.h.as we go around our local star and spinning at an equatorial speed of approximately 1000 m.p.h. It causes massive distortions, like a weight on a sheet of rubber, any smaller object falling into this distortion, this, "gravitational well", will need to expend a lot of energy escaping or fall to the centre. This is why planet Earth attracts "junk" from the stars

don't forget the gravity!!!!!

it's not caused by magnets. It is caused by nature, but u can always see it happen. for example, if u throw up a leather ball instead of moving up,actually it's moves up, but when it gets to a certain height the force of gravity is high on it and so the object is returned back to the earth. it's not the earth that attracts, it's the force that pulls back.Space rocket that are launched are moved at at a very great speed to escape the earth's gravity.the gravity of the moon is about one-sixth of the earth's what causes gravity, we don't know maybe if there wasn't any force called gravity, probably we would have been floating. We cant even measure gravity waves, but it's possible to escape it's force