The quasi-coherent modes (QCMs) was observed by the multi-channel three-wave polarimeter-interferometer system (POLARIS) based on the spectra analysis of density fluctuation in J-TEXT. The frequency range of QCMs is 30kHz to 100kHz and located at the minor radius r about 0.45a-0.7a in the interior of plasma in each disruptive shots. The QCMs are found related to the density, and it can be observed in each density limit disruptive shots while not onset in some undisruptive shots.The QCM enhancement occurs well before MARFE onset in density limit disruptive shots.