The average spacesuit in use today weighs approximately about 128 Kg.
In other words, it could actually be heavier than the astronaut himself, by as much as two times. The suit has around 11 layers of material to give its thickness and weight. It is made up of complex strength compound materials.
At the same time, however, it is not really much of a problem when you are in space. Given that there is almost no gravity, the weight of the space-suit is not going to mean much when you are up there.