A valid marriage must have the following requierements in Islam:
1. Both man and woman must be free from any legal prevention to their being able to marry one another
2. The acceptance of woman's guardian.
There are 4 conditions of marriage:
1. The presence of both couples
2. Their approval
3. The presence of the woman’s guardian
4. Two male witnesses there must be Muslims
Our Prophet Mohammed (peace be upon him) said : “Any woman married without the consent of her guardian, then her marriage contract is void , and the ruler is the guardian for whom has no guardian”. He also said: “There is no marriage without a guardian.”