The present invention relates to an acyclic nucleoside phosphonate derivative and medical uses thereof. Specifically, the present invention relates to an acyclic nucleoside phosphonate derivative of Formula I having strong potency against viruses, such as hepatitis B virus, and low cytotoxicity, or a pharmaceutically acceptable salt, isomer, hydrate or solvate thereof, wherein R1 is H or methyl； each R2 is independently —R3 or —OR3, each R3 is independently C1-C8 alkyl, C3-C8 cycloalkyl. The present invention further relates to a process for preparing the compounds of Formula I, a pharmaceutical composition comprising the compound, and the medical uses of the compound. The acyclic nucleoside phosphonate derivative of the present invention has activity against virus such as hepatitis B virus and good in vivo behavioral traits.
