Provided is a quinoline derivative of Chemical Formula (I):
wherein, R
1
is a substituted or unsubstituted phenyl group, R
2
is a halogen, and R
3
is a substituted or unsubstituted phenyl group, and one of the carbon atoms in the phenyl ring of the phenyl group is optionally substituted by a nitrogen atom (N). The quinoline derivative can efficiently inhibit cancer cell proliferation and can be used for treating cancer, especially for treating cancers related to the Janus kinase-signal transducers and activators of transcription (JAK-STAT) pathway and/or the mitogen-activated protein kinase (MAPK) pathway.