Abstract: In order to formulate effective countermeasures for biodiversity conservation and provide biodiversity conservation with better theoretical reference, the characteristics of landscape pattern and its scale effect of Bitahai Nature Reserve were studied. Based on the spatial attribute database of subcompartment from class II forest resource survey in Shangrila County, Yunan Province in 2006, the spatial variation in landscape diversity and patch density of Bitahai Nature Reserve was analyzed at 4 different scales with the help of ArcGIS analysis and the semivariation functions in geostatistics. The results showed that as the scale changed from 400m to 800m, 1200m and 1600m, the value of C0 /(C+C0) for landscape diversity index SHDI changed from 048287 to 078522, and the ratio value decreased along with the increase of the scale. The ratio value of C0/(C+C0) for patch density index decreased from 076592 to 076592, the C0 value increased as the scale increased. When the scale was 1600m, the C0 value dropped suddenly, whose change was not in conformity with the law of semivariable function. 1200m was the optimal scale for the specific study, under which the SHDI of the nature reserve was distributed in a circular form, whose maximum value of C0 dropped gradually from the west part of the nature reserve to the peripheral zones. The maximum value of patch density appeared in the northern area of the reserve center, which was also decreased gradually from the central part of the nature reserve to the peripheral areas. The distribution of SHDI and PD values was comparatively even, and not polarized.