This paper introduces an advanced dual-modality imaging platform by integrating a confocal laser scanning/imaging module with flat-fielding quantitative phase contrast microscopy (FF-QPCM). The platform enables phase/fluorescence dual-modality imaging of the same samples with high resolution and contrast. Using this platform, we observed that confocal fluorescence excitation causes minimal damage to cells, whereas wide-field fluorescence excitation results in significant damage, particularly mitochondrial fragmentation and notable alterations in phase values. Additionally, in situ quantitative phase imaging was conducted on live COS7 cells with a specific region irradiated by a confocal laser. The results demonstrated that 5-minute continuous confocal laser irradiation affects only COS7 cells with fluorescently labeled mitochondria, causing mitochondrial dysfunction throughout the cell. These findings suggest that integrating FF-QPCM with a confocal laser scanning/imaging module offers a highly efficient, sensitive, and information-rich tool for cell biology research, with broad application potential.