That depends on where the water is coming from. Water is a powerful force.
If it's the water table rising up, it may not be solvable. So the first thing is to find out where the water is coming from.
If this is a new problem and only happens during a rain storm, then it's surface water and may be coming off your roof. This being the case you just need to divert the water away from you foundation. This can be done by extending the downspouts into either underground pipes that lead away from the house or by simple plastic extensions that are moveable for cutting the grass. You should also check to make sure that your gutters are clean, installed, and pitched correctly. You may want to consider a gutter protection system like Leaf Relief if you get a lot of leaves.
Check to make sure your foundation is not cracked. If you have a small surface crack you can probably patch it your self with some hydraulic cement (available at any hardware store or box store)
If it's a water table problem, you may need a sump pump, or have a French drain installed. This will entail digging a pit below the floor surface and recessing a barrel down to house the pump and then running a pipe from the pump out of the foundation and away from the house. If you are A DIY person you could probably handle this or many professional plumbing or basement waterproofing companies (like Basement Technologies) offer this service. It's a good idea to get a battery backup for the pump as well.
If the basement leaks only during heavy rains, this can lead to basement flooding, and the proliferation of mold and mildew. This not only compromises your house's structural integrity, it also is a health hazard to you and your family.