Here I introduce some examples of molecular structures related to disease therapy. One is oseltamivir which is also given the trade name Tamiflu. The important processes of influenza infection are to ENTER the host cell and to GO OUT from it, and some of the antiviral medicines target these processes. The enzyme neuraminidase clips off a sialic acid from the cell membrane to assist the replicated viruses to go out. Tamiflu is a molecule with a similar structure to it which also binds to neuraminidase, and inhibits the enzyme function (Figure 1). In the case of mutant enzyme (H274Y), Tamiflu binds to it weaker than the wild type, so Tamiflu has less effect than the mutant type. The replaced 274th residue tyrosine is bulkier than the original amino acid histidine and causes orientation change of the amino acid at the active site (Figure 2). Another example is involved in Ebolavirus causing epidemics in West Africa. Although the effective therapeutic medicine and vaccine have not been found yet, the molecular structure of the antibody complex with virus glycoprotein from a human survivor is already deposited to PDB (Figure 3). Now scientists are searching for some effective chemicals and methods using this information.