Background. Despite the presence of robust evidence, very sparse data are available on the efficacy of allergen immunotherapy (AIT) on selected patients in  real-life. Moreover, the obtained data does not ever fit with the general population; thus, the translation and the use of data obtained from randomized clinical trials (RCTs) in  real-practice can be questionable. Accordingly, we aimed to evaluate in  real-life efficacy and perceived satisfaction of 3-year sublingual immunotherapy (SLIT) in a pediatric population with with allergic rhinitis and/or asthma. Methods. A pilot, monocenter, retrospective cohort,  real-life study was performed. 153 children who fulfilled the criteria for allergic rhinitis and asthma and mono- or poly-sensitized were enrolled. A standardized questionnaire on perceived efficacy, rescue medication, disease control, number of exacerbations, quality of life, and perceived satisfaction was administered to each patient. Results. 70 patients (49 males, 21 females; mean age, 14.3±1.9 years) were included in the final analysis. All 70 patients received SLIT for up to three years, with 100% treatment adherence throughout the study duration. Significant improvement in symptoms and quality of life was reported (p<0.01). A significant decrease in disease severity, rescue medication use, and sleep disturbances was reported (p<0.01). A significant improvement was also recorded in school performance (p<0.01).  60/70 (85.7%) of all enrolled patients declared themselves  very  satisfied, 6/70 (8.57%)  much satisfied, and 4/60 (5.71%)  satisfied.  Conclusions. We firstly showed the efficacy and perceived satisfaction of 3-year SLIT in a paediatric population, with 100% treatment adherence throughout the study duration, in  real-life.