Abstract: The effectiveness of patent infringement relief depends largely on the judicial judgment of the amount calculation of patent infringement damage compensation. On this issue, Japan has formed a more appropriate institutional framework from substantive law to procedural law through twentyyear developmentafter the revision of the patent law and provided scientific evaluation criteria in encouraging innovation and restraining infringement. More importantly, from concept it broke through the shackle of traditional tort law taking“damage to fill” as the sole function, explored the best possible future inhibition of possible infringementthrough the damage compensation system, a variety of damages calculation methods,including the actual loss of obligees, the infringers’profits, and reasonable multiples of the license fees, areunified tocurb infringement system purposes.

Key words: compensatory damages, optimal inhibition, punitive damages, opportunity cost, damage calculation methods