Potassium channels include several families: Ca²⁺-activated (KCa), inward-rectifying (KIR), two-pore (K2P) and voltage-gated channels (Kv). Three of these families has been described in adipocytes. In this work we try to characterize the Kv channels present in white adipocytes from the epididymal fat pad of male Wistar rats. Preadipose cells were obtained and plated in coverslips, where they differentiate in 3-6 days. Voltage-clamp recordings in the whole-cell configuration were performed to analyze the expressed Kv channels. Tail currents showed a monoexponential deactivation in 93 % of the cells, with a time constant of 2.23 ± 0.23 ms (mean ± S.E.), in pulses from + 60 to –110 mV. This would suggest that in most cells there was only one type of Kv channel. Nevertheless, in pulses of 10 s from a holding potential of –70mV to + 20 mV, the time-dependent inactivation presented a biexponential course, with time constants of 0.55 ± 0.13 s and 4.49 ± 0.92 s. Two phases can be observed in the voltage-dependent inactivation from –120 mV. The first from –110 to –50 mV, the second from here to 0 mV. From 21 cells, 5 % only exhibited the first phase, 9.5 % only the second, 19 % both and the majority (66.5 %), presented a mild first phase followed by a clear second phase. We conclude that most cells express only a Kv channel, compatible with the Kv 1.5 type, though this does not preclude the expression of potassium channels from the other families.