Abstract: Objective To explore the correlation between vitamin A (VA) level and Mycoplasma pneumonia (MP). Methods Children aged 0-12 years hospitalized with acute infectious respiratory diseases during March 2015 to December 2015 were randomly selected. The level of serum VA was detected by high performance liquid chromatography (HPLC). MPDNA on nasopharyngeal swab was detected by polymerase chain reaction (PCR). The serum MP-IgM was detected by enzyme linked immunosorbent assay (ELISA). The MP infection rate among subclinical VA deficiency (SVAD) group, suspicious subclinical VA deficiency (SSVAD) group and VA normal group were analyzed and compared. Results Among 600 children, there were 83 cases of SVAD (13.83%) and 193 cases of SSVAD (32.17%). There were statistical differences of the incidences between SVAD and SSVAD in children younger than 1-year-old, 1-3 years old, 3-6 years old and ≥6 years old (P all ＜ 0.001), among which SVAD and SSVAD groups had the highest incidence rates in infants younger than 1 year old (26.36% and 49.10% respectively). Among 600 children, MP was positive in 201 children (33.5%),  in whom 57 children (28.35%) were SVAD and 70 children (34.83%) were SSVAD. The incidence rate of SVAD in children with MP positive was higher than that in children with MP negative (P ＜ 0.001). In 201 children with MP positive, there were significant differences in the distribution of SVAD, SSVAD and VA among different age groups (P =0.003), and the incidence rate of SVAD in infants younger than 1 year old was higher (48.39%). Conclusions SSVAD and SVAD are common in infants younger than 1 year old; SVAD may be associated with MP infection in children.