You will be required to appear for MCAT exam to get admission in HARVARD MEDICAL SCHOOL.

Factors considered for selection are:

The Committee on Admissions evaluates applications based on several factors, including the following:

• Academic records
• Applicant essay(s)
• MCAT scores
• Letters of evaluation
• Extracurricular activities
• Summer occupations
• Life experiences
• Experience in the health field, including research or community work

You can even check the complete details here .