Cellular elasticity is a key factor related to a broad range of physiological and pathological processes. The elasticity of a single cell has thus emerged as a potential biomarker to characterize the cellular state. Both internal and external stimuli affect cellular elasticity, and changes in elasticity can cause alterations in cellular characteristics or function. The application of electric fields (EFs) is a promising method that can be used to change cellular elasticity; however, the mechanisms underlying its effect remain unknown. Here, we demonstrate EFs-induced elasticity changes in human dermal fibroblasts and discuss the underlying mechanism related to actin polymerization. Cellular elasticity increases after EF (50 mV/mm) stimulation, reaching a maximum at 30 min before decreasing between 30 and 120 min. The cellular elasticity under EF stimulation, regardless of stimulation time, is higher than that of the control. F-actin regulates the elasticity of cells through gelsolin activation. We show changes in intracellular Ca²⁺ caused by EFs, which induced gelsolin activation and F-actin content changes. This result demonstrates a series of processes in which external electrical stimulation conditions regulate cellular elasticity.