Can the ex wife inherit the estate when the exhusband died without a will?

You would need to consult an attorney (lawyer), but probably not as the wife is no longer next of kin. When someone dies intestate (without a will) the property is managed by the state who will distribute it to the deceased's next of kin (children first, then brothers sisters - cousins etc) following the laws of the country. An ex wife is no longer really in the picture - BUT if you have had children with the husband, they will be entitled to inherit.

However, an ex-wife could calaim against her deceased ex-husband's estate for child support arrears or for financial obligations in the divorce decree that were not satisfied. If you feel this applies to you, you should consult with your divorce attorney who could review your situation and determine what your options are.