Without any facts, it is difficult to furnish specific advice, or even to know which statute to apply. Nonetheless, if you are being treated worse than other employees based on race, gender, creed, age, or national origin (each of these, a protected class), you have a right to file a complaint with the Equal Employment Opportunity Commission (EEOC). The EEOC will then either decide to proceed against the employer or will furnish you with a right to sue letter, which will give you the ability to bring your claim in court.
You should be aware that discrimination is difficult to prove, and the courts are generally predisposed against it, in large part because anti-discrimination laws are so often abused. You should carefully consider two factors before deciding to proceed. First, has your employer made disparaging comments about you based on your age, race, gender, creed, or national origin. Second, are you being treated worse that comparably placed employees (i.e., same or very similar job) who do not share the characteristic that is the focus of the discrimination (such as race etc.). Things to look out for include being disciplined for conduct tolerated from workers outside the protected class or for conduct that the employer/manager has engaged in.
Employees who bring discrimination charges against their employers are frequent targets for termination. Even though technically illegal, this claim can also prove difficult to establish. So I would be cautious when proceeding. Discrimination law is complex and has more than its fair share of pitfalls. I would strongly recommend that you speak with a labor and employment or civil rights attorney in your area before you proceed with any formal action.
In general, in order to determine whether you have any legal basis for a claim against your employer, you must determine the motive for the unequal treatment. Once you identify the motive, a lawyer who handles employment cases in your state can tell you whether there is any law protecting you from the unequal treatment.