Thermopower of pure metals of Fe ，Co and Ni were measured in the vicinity of Curie temperatures.The results show that the curves of thermopower against temperature behave very similarly, being concave first and convex subsequently. Consequently, three special points for each metal can be determined by the corresponding curve, namely the ferromagnetic Curie temperature Tf, Curie temperature TC, and paramagnetic Curie temperature θp. It is obvious that there is a definite transition interval of temperature between ferromagnetic state and paramagnetic state of the metal and the Curie temperature is only an intermediate value. A discussion is made which concludes that the holes in the d band contribute to the electrical conduction in the temperature interval between Tf and TC, which implies that the magnetic carriers are the holes. It is also contemplated that there may exist short range order between TC and θp.