Oseltamivir phosphate (OSP), marketed under the brand name of Tamiflu®, is a potent inhibitor of viral neuraminidase, a glycoside hydrolase enzyme essential for viral replication. OSP is also important to control influenza virus (H1N1) and is produced mainly from shikimic acid (SA) extracted from plants. The main source of SA is from seeds of I. verum. Alternatives to meet the worldwide demand are necessary. One of this is Cryptomeria japonica. Inthis study, we found a content of 56.36 mg.kg-1 of SA in dried biomass for C. japonica, while for I.verum, the traditional source, was 96.57 mg.kg-1. Due to the fact of C. japonica is a tree, exploited for commercial production, it can be a renewable and reliable source SA for OSP production.