Tannins can be obtained from almost all kinds of green plants, plants low level and high level with varying levels and quality. Tannins are polyphenolic compounds that are very complex. Because of the phenol group, the tannins can react with formaldehyde (condensation polymerization) to form thermosetting products that can be used as an adhesive. Antibacterial effectiveness of tannin contained in the leaves of plants such as guava is influenced by the concentration of tannins. The higher levels of tannin antibacterial activity will increase. Because of its importance in the treatment of guava leaf, the quality, safety and benefits should be improved through research and development. To improve the quality, safety and effectiveness of guava leaves as a natural medicine Indonesia, standardization needs to be done to the raw material, either in the form or in the form of crude drug extracts or galenic preparations. One of the factors that affect the quality of medicinal plant extracts is the concentration of the solvent used for extraction (Gaedcke et al., 2003)[13]. It is therefore necessary to study to determine the concentration of organic solvent for efficient extraction of tannins from guava leaves extract in order to get good quality. This study aims to determine the type of solvent with a suitable concentration to obtain tannin extract of guava leaves are good quality. Quality parameters of guava leaf extract is measured is the acquisition of extractive (yield of extract) and levels of tannins in leaves of guava.