β-Galactosidase Reporter Assay Kit is a kit for the detection of the β-galactosidase reporter gene using colorless ONPG as substrates. β-galactosidase is a commonly used reporter molecule that can be used to transfect cells with the luciferase reporter and serve as an internal control for the luciferase reporter, thereby eliminating experimental errors due to differences in transfection efficiency. The substrate provided in this kit produces a yellow product catalyzed by β-galactosidase, and the activity of β-galactosidase can be determined by measuring the absorbance at 420 nm. The lysis buffer provided in this kit is suitable for the lysis of animal cells, plant cells or tissue samples.