There is an ongoing effort to apply methods based on nonlinear dynamics to improve the description and classification of different states and diseases. Relatively few studies were focused on autonomic neuropathy in young adults with diabetes mellitus (DM) type 1. The aim of this study was to find out which of the heart rate variability parameters derived from recurrence plot (recurrence ... [Show full abstract] quantification analysis parameters) are different in young patients with DM compared to control group. We have quantified various recurrence plot measures. From RQA measures based on diagonal lines in recurrence plots, we have found higher percentage of recurrence and of determinism and increased maximal length of diagonal line in DM group. Parameter Trapping Time was higher in DM group compared to control subjects. These results suggests reduced complexity and increased predictability of heart rate dynamics even in young patients with DM. RQA parameters should be used together with other HRV parameters for better description of heart rate dysregulation in various patients groups.