Abstract
The financial system governing over the spouses may be divided into conventional and legal categories where the conventional system is caused by agreement due to will of spouses as well as the principle of free will; of course, there is not free will in determination of financial relations among the spouses in Iranian and British laws for marriage as it exists in other contracts and this is also because of the certain sensitivity that is enforced by the legislator regarding this subject. The legal system that governs over the relations between spouses may be employed where there is no agreement among the spouses and/ or the existing agreement is assumed void legally. The legal system includes several types either of which possesses certain conditions and effects but what it has been accepted by Islam from the beginning and Iranian law since the date of existence as well as in British law since several decade ago is concerned with financial independence of the married woman (separation of properties), which include many advantages and at the same time it suffers from some disadvantages, which can be resolved by means of legal awards, case law as well as certain powers in the courts concerning to adjustment of financial rights for the spouses. However, properties separation system is the acceptable financial system currently in British and Iranian laws; this does not bar spouses’ agreement for joint investment and the granting gift by either of them and other agreement within legal limits.