  We present scanning tunneling microscopy and spectroscopy measurements on a
cleaved surface of the LaO0.9F0.1BiSe2 single crystals. Tunneling spectra show
a finite local density of states at EF, which is consistent with metallic
conductivity in bulk. In addition, the existence of the supermodulation running
along the diagonal directions of Bi square lattice was revealed. The period of
the supermodulation was about 3 to 5 times the length of the lattice constant.
This period is close to that observed in LaO0.5F0.5BiSe2.
