Chronic apical periodontitis (CAP) is characterized by tissue inflammation around the tooth tip. Unstable outcomes of current treatments against CAP dictate the need for novel therapeutic techniques and medications. The aim of this study was to analyzed the effects of hirudotherapy on the treatment course in patients with CAP. Forty-one study participants aged 25 to 40 years were divided into the main group (20 patients) and the control group (21 patients). Pain level and the gingival index (GI) were measured in all study participants. During the first visit, pain scores did not differ significantly between the control (5.81 ± 0.65) and the main (5.75 ± 0.92) groups. During the second visit, pain was almost unnoticeable in the main group patients (1.05 ± 0.34), whereas pain scores were higher in the control group (4.10 ± 0.7). Our findings suggest a positive effect of hirudotherapy used in combination with standard treatment regimens.