If one partner is Japanese, under Japanese law if the custodial parent (shinken-sha = 親権者) requests child support (yoikuhi = 養育費) then the non-custodial parent is required to pay child support to the custodial parent. The amount of child support will depend on the parent's income and the individual needs of the child/children.

The amount is generally decided between the parties involved, however, if both parties cannot agree the issue must be settled in the family court. Alimony (isharyo = 慰謝料) can also be claimed if a partner has been unfaithful, violent, committed illegal acts, or done something that resulted in responsibility for the divorce.

Alimony is generally a one-time lump sum payment (in some cases it can be broken down into monthly or periodic payments) for pain and suffering on part of the injured party (e.g. spouse). Please be aware that there are times when alimony is not paid, it is not a given in Japan. Once again, if an amount cannot be agreed upon you will be required to go to the family court for mediation, and if an agreement still can't be reached it may be necessary to re-file a lawsuit with the family court.