In this work, we present the new catalog of carbon stars from the LAMOST DR2 catalog. In total, 894 carbon stars are identified from multiple line indices measured from the stellar spectra. Combining the CN bands in the red end with ctwo and other lines, we are able to identify the carbon stars. Moreover, we also classify the carbon stars into spectral sub-types of ch, CR, and cn. These sub-types approximately show distinct features in the multi-dimensional line indices, implying that in the future we can use them to identify carbon stars from larger spectroscopic datasets. Meanwhile, from the line indices space, while the cn stars are clearly separated from the others, we find no clear separation between CR and ch sub-types. The CR and ch stars seem to smoothly transition from one to another. This may hint that the CR and ch stars may not be different in their origins but look different in their spectra because of different metallicity. Due to the relatively low spectral resolution and lower signal-to-noise ratio, the ratio of $^{12}$C/$^{13}$C is not measured and thus the cj stars are not identified.
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