In this study, a fabrication method for a system composed of a fluorescence imaging module and a multielectrode array (MEA) chamber is described. It is important to measure both fluorescence intensity and electrical activity to obtain a better understanding of a physiological activity, such as spikes or action potentials, of cells. However, observing these physiological traits long-term with cultured cells is difficult using a conventional microscope. In this study, we developed a small fluorescence imaging device with an MEA that can be used in a conventional CO2 incubator. The fluorescence imaging module was composed of a CMOS image sensor, a fiber-optic plate (FOP), a blue LED, and optical filters. The FOP enabled the device to be miniaturized through lensless fluorescence imaging. The MEA chamber was fabricated with micro gold electrodes deposited on the FOP. By using the FOP for the bottom of the chamber, we measured both the fluorescence signal and electrophysiology signal in the same experiment. The performance of the device was evaluated with neuronal blastoma cells. Our device enabled us to observe fluorescence images and MEA signals.