Signal transducer and activator of transcription 5 (STAT5) is a transcription factor that is involved in various cellular processes, including cytokine signaling, immune response, hematopoiesis, and cell proliferation. The STAT5 luciferase reporter vector is designed to study the transcriptional activity of STAT5. The vector contains a STAT5 DNA consensus binding site and TA minimal promoter upstream of a firefly luciferase reporter gene, which can specifically report STAT5 activity while maintaining a low basal level of transcription.