Possibly. Although an employer may deduct the cost of your uniform from your paycheck, it can be illegal under certain circumstances. The Fair Labor Standards Act makes it illegal for your employer to require you to wear a uniform, and then deduct it from your wages IF it causes your wages to fall below the minimum wage standard. Further, it is also illegal for your employer to make any profit on the uniform by deducting it from your wages.
Some states have passed laws prohibiting employers from being able to deduct the cost of uniforms from wages, but these laws are often narrow and do not provide broad protection. However, there have been successful lawsuits challenging employers' requirements that retail employees wear the clothing sold by their employers, in order to have the store's look.