Dysregulation of peroxisome proliferator-activated receptor (PPAR)-γ has been described in a plethora of pathological conditions, such as diabetes, obesity, inflammatory-related diseases, and cancer. Therefore, identifying novel drugs that are able to restore PPAR-γ activity is a current challenge, which is however slowed down by the lack of a rapid and reproducible activity assay. To date, only a few methods are able to characterize PPAR-γ activity and most of them are expensive, time-consuming, and not always quantitative.Herein, we presented a sensitive multi-well colorimetric assay, termed DNA-Protein-Interaction enzyme-linked immunosorbent assay (DPI-ELISA). This method is based on the ELISA principle, except that it allows to detect only activated PPAR-γ because, unlike classical ELISA, PPAR-γ is not captured by an antibody but by a double-stranded oligonucleotide probe containing its peroxisome proliferator response elements (PPRE) consensus sequence. Thus, DPI-ELISA represents a useful assay for PPAR-γ studies, as well as for the identification of novel PPAR-γ ligands for the development of innovative therapeutic approaches to human diseases where PPAR-γ signaling is dysregulated.