Abstract. Spectroscopic observations of off-limb corona have been done using 25 cm chronograph of National Astronomical Observatory, Norikura, Japan. Raster scans were made using forbidden iron lines in optical regime, namely [Fe X] 6374 A^o (red line), [Fe XI] 7892 A^o, [Fe XIII] 10747 A^o and [Fe XIV] 5303 A^o(green line), with two lines simultaneously. Using those scans from mid-latitude to polar regions taken in September 2004, the variation of intensity ratios and spectral line widths with height and from structure to structure are studied. The results indicate that the line width of green line decreases with height whereas that of red line increases and the other two lines show intermediate behavior irrespective of the structure. Also, the intensity ratio of green line to red line decreases with height whereas that of other two increases with respect to red line. The possible explanation suggested for this complex behavior including the comparison of the gradients from structure to structure and also with the earlier equatorial region results will be discussed.