Article II Section 1 of the Constitution states and sets the qualifications to be President. It states that: No person except a natural born citizen, or a citizen of the United States, at the time of the adoption of this Constitution, shall be eligible to the office of President; neither shall any person be eligible to that office who shall not have attained to the age of thirty-five years, and been fourteen years a resident within the United States.
Additionally, the 22nd Amendment sets the term limits for President.