Intrabody communication (IBC) is an effective way to connect various kinds of wearable devices attached on or under the surface of the body, but it is important to quantitatively evaluate the biological effects of the IBC signal on the human body before its further application. The research described in this paper analyzed the responses of HSF (human skin fibroblast) cells exposed to IBC electrical signals. A galvanic coupling IBC signal transmitting system was designed to expose the experimental samples with different amplitudes (from 0 V to 6 V or 0 mA to 4 mA), different frequencies (from 10 kHz to 1 MHz), and different duration times (12 h and 24 h). The control groups were unexcited. Cell morphology and activity were evaluated with inverted microscope and MTT assays. The cell survival rates of all the experiment groups were in the range of 90% to 110%. Then, the data was analyzed by t -tests to assess whether there were statistically significant differences. The results showed that p values were greater than 0.05, so there were no significant differences between the experimental and control groups. Therefore, it can be concluded that the IBC signals do not have a significant effect on HSF cells.