The assessment of quality of life (QoL) is an indicator of the effects of treatments. The aim of our study was to construct a new test, the DIAbetes and quality of Life (DIAL) questionnaire, to assess the QoL perceived in patients with type 1 diabetes. 298 type 1 diabetes are enrolled. DIAL total score was (median [quartiles]) 220 [114,251]; “A” score was 34 [16, 62] and mean “B” score was 63 [18,81]. A significant correlation between test and re-test scores was observed. Results of factor analysis were compatible with a 2 factor-structure. Factor 1 accounted for 30.6% of variance and factor 2 for 7.5%. Individual items were assigned to two different subscales. DIAL showed a significant direct correlation with DQOL total scores and with Impact, Preoccupations, and Diabetesrelated preoccupation subscale scores. Significant direct correlations of DIAL and its subscales were also found with SF-36 whereas an inverse correlation was observed with HbA1c and DQOL Satisfaction score. No correlation was found with BMI or age. HbA1c showed a direct correlation with DIAL 1 and total scores, as well as with DQOL satisfaction score, and inversely correlated with DQOL-Diabetes-related concern scores. Differences in either DQOL or DIAL scores between patients with and without complications were not statistically significant; DQOL, showed a significant difference between genders. DIAL has demonstrated to be more useful for the actual type 1 diabetes management and the adoption of instruments which take into account the subjective relevance of different areas, could provide a greater accuracy in measurement.