Abstract: The extensible support pole unit having a simple structure including a plurality of shaped members, e.g., cylindrical bodies, band-like plates having, e.g., an arched cross-sectional shape, a band-like plate feed mechanism, and a driving device. The support pole is extended to stand or retracted by only paying out or winding up the band-like plates. The support pole can therefore be extended to a length freely selected, and it is possible to freely set a large extension ratio by selecting the length of each cylindrical body and the number of cylindrical bodies. The band-like plates have, for example, an arched cross-sectional shape and have properties such as to be strong against the vertical load as compared with flat plates. The band-like plates are retained in the guide slits or guide holes formed in the partition members disposed in the cylindrical bodies to further improving the above properties.