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We present a catalogue including 11,204 spectra for 10,436 early-typeemission-line stars from LAMOST DR2, among which 9,752 early-type emission-linespectra are newly discovered. For these early-type emission-line stars, wediscuss the morphological and physical properties from their low-resolutionspectra. In this spectral sample, the H$\alpha$ emission profiles display awide variety of shapes. Based on the H$\alpha$ line profiles, these spectra arecategorized into five distinct classes: single-peak emission, single-peakemission in absorption, double-peak emission, double-peak emission inabsorption, and P-Cygni profiles. To better understand what causes theH$\alpha$ line profiles, we divide these objects into four types from the viewof physical classification, which include classical Be stars, Herbig Ae/Bestars, close binaries and spectra contaminated by HII regions. The majority ofHerbig Ae/Be stars and classical Be stars are identified and separated usingthe (H-K, K-W1) color-color diagram. We also discuss thirty one binary systemsas listed in SIMBAD on-line catalogue and identify 3,600 spectra contaminatedby HII regions after cross matching with positions in the Dubout-Crilloncatalogue. A statistical analysis of line profiles versus classifications isthen conducted in order to understand the distribution of H$\alpha$ profilesfor each type in our sample. Finally, we also provide a table of 172 spectrawith FeII emission lines and roughly calculate stellar wind velocities forseven spectra with P-Cygni profiles.

A catalogue of early-type emission-line stars and H{\alpha} line profiles from LAMOST DR2