This study reports a transparent indium tin oxide (ITO)-based microheater chip and its applicability for perfusion cell culture outside a cell incubator. The attempt of the proposed ITO microheater is to take the role of conventional bulky incubator for cell culture in order to improve integratability with the experimental setup for continuous/perfusion cell culture, to facilitate microscopic observation or other online monitoring activities during cell culture, or even to provide portability of cell culture operation. In this work, numerical simulation and experimental evaluation have been conducted to justify that the presented device is capable of providing a spatially uniform thermal environment and precise temperature control with a mild deviation of +/-0.2 degrees C, which is suitable for a general cell culture practice. Besides, to testify that the thermal environment generated by the presented device is well compatible with conventional cell incubator, chondrocyte perfusion culture was carried out. Results demonstrated that the physiology of the cultured chondrocytes on the developed ITO microheater chip was consistent with that of an incubator. All these not only demonstrate the feasibility of using the presented ITO microheater as a thermal control system for cell culture outside a cell incubator but also reveal its potential for other applications in which excellent thermal control is required.