From February to May 2018, an Algorithm Competition on spectral classification was organized by China-VO and Alibaba Cloud. Around 1000 people (over 800 teams) from the public has participated in the competition, applying machine learning technique on LAMOST spectra dataset to automatically classify the spectra into star, galaxy, quasar and unknown. The winner team employs deep neural networks to solve the problem and achieves an overall macro-F1 score of 0.83.