The invention discloses a C3/C3 fluoroquinolone dimmer derivative using oxadiazole as a connection chain as well as a preparation method and an application thereof. The C3/C3 fluoroquinolone dimmer derivative using oxadiazole as a connection chain is a compound which has the following structural general formula (I), wherein R1 and R1' are independently selected from H, (C1-C10) alkyl, (C3)-(C10) cycloalkyl, (C1)-(C10) haloalkyl and substituted aryl group or substituted heterocyclic aryl group; R2 and R2' are independently selected from H, (C1-C7)alkyl, (C3)-(C7) cycloalkyl, substituted aryl group, substituted heterocyclic aryl group and hydrocarbon acyl or sulfonyl; R3 and R3' are independently selected from H, (C1-C5) alkyl, (C3)-(C5) cycloalkyl, substituted aryl radical or substitutionalheterocyclic aryl radical; and X and Y are independently selected from CH, N or carbon atoms connected with halogen, alkyl, oxyl, sulfenyl, amino, substituted amino, substituted aryl radical or substituted heterocyclic aryl radical. The C3/C3 fluoroquinolone dimmer derivative using oxadiazole as a connection chain can be used for preparing medicaments for treating tumors and preventing microbialinfection diseases.