Objective  To explore differences in mental health service (MHS) acquisition and demand between rural left-behind and non-left-behind school children and to provide evidences for establishing MHS system.

  Methods  We conducted a self-administered questionnaire survey among 3 456 primary school students of grade 4 to 6 and junior high school students of grade 1 to 3 selected in 14 schools in rural areas of Sichuan, Anhui and Henan province with stratified random cluster sampling between April and July, 2018. We used a self-designed questionnaire to assess MHS acquisition and demand among rural left-behind and non-left-behind school children.

  Results  Among the 3 146 eligible participants, there were no significant differences between left-behind and non-left-behind school children in MHS acquisition rate (27.9% vs. 27.0%), introducers of MHS providers, effect assessment on MHS received, and the way to get MHS acquisition channels (P > 0.05 for all). But there was a significant difference in the rate of MHS between left-behind children and non-left-behind school children (63.0% vs. 57.2%) (P = 0.001); significant differences were also found in demands of following 6 MHS items between the two groups of the school students: improving anxious or depressive emotion, overcoming stress symptoms when answering questions or talking with strangers (including nervousness, red face or heartbeat, sweating, and stuttering), changing passive attitude towards things encountered, self-affirmation, developing a strong mind of self, avoiding being bullied, and ways to cope with stress or other bad things (P < 0.05 for all).

  Conclusion  There are obvious disparities in acquisition rate, ways, and demands of mental health service between rural left-behind and non-left-behind school children; the rural left-behind school children need more mental health service, especially self-improvement-related items, than the non left-behind children.