You may be eligible for a green card through your family, employment, refugee or asylum status.
Eligibility for an Immigrant Category

I. Family Based

Immediate relatives of a U.S. citizen are given the highest priority and do not have to wait for a visa to become available. There is no limit to the number of visas that can be utilized in this category in a particular year.
They are:

• Parents of a U.S. citizen (U.S. citizens must be at least 21 years old to apply for their parents)
• Spouses of a U.S. citizen
• Unmarried children under the age of 21 of a U.S. citizen

Other qualified relatives of a U.S. citizen or permanent resident in the remaining family-based categories may have to wait for a visa to become available before they can apply for permanent residency.
They are:

• First Preference: Unmarried, adult (21 years of age or older) sons and daughters of U.S. citizens
• Second Preference A: Spouses of permanent residents and the unmarried children (under the age of 21)) of permanent residents
• Second Preference B: Unmarried sons and daughters (21 years or age or older) of permanent residents
• Third Preference: Married sons and daughters of U.S. citizens, their spouses and their minor children
• Fourth Preference: Brothers and sisters of adult U.S. citizens, their spouses and their minor children

II. Job or Employment Based

Employees who want to become immigrants based on employment or a job offer may apply for permanent residence or an immigrant visa based on:

• First Preference: Priority Workers, including aliens with extraordinary abilities, outstanding professors and researchers, and certain multinational executives and managers
• Second Preference: Members of professions holding an advanced degree or persons of exceptional ability (including individuals seeking a National Interest Waiver)
• Third Preference: Skilled Workers, professionals and other qualified workers
• Fourth Preference: Certain special immigrants including those in religious vocations
• Fifth Preference: Employment creation immigrants (investors or entrepreneurs)

III. Based on Refugee or Asylum Status

If you were admitted to the United States as a refugee or the qualifying spouse or child of a refugee, you are required to apply for permanent residence (a green card) 1 year after your entry into the United States in this status. If you were granted asylum in the United States or are a qualifying spouse or child of an asylee, you may apply for permanent residence 1 year after the grant of your asylum status.

If you are a refugee, you are required by law to apply for a green card 1 year after being admitted to the United States in refugee status.
If you are an asylee or asylee derivative spouse or child, you are not required to apply for a green card 1 year after being granted asylum or 1 year after being admitted to the United States in asylum status, although it may be in your best interest to do so.