Introduction and objective: Erectile dysfunction has become an increasingly common issue and is predictive of various cardiovascular and mental conditions. This study focuses on low-intensity extracorporeal shock wave therapy (Li-ESWT), which is recognised by the European Association of Urology as an adjunct to first-line treatment for erectile function. Li-ESWT can be an alternative to or complement pharmacotherapy (phosphodiesterase type 5 inhibitors). It is painless, non-invasive, and safe for the patient, as confirmed by numerous studies. Material and methods: The study included a group of 40 men receiving Li-ESWT treatment once a week. Treatment parameters were established based on the Motil algorithm following a qualifying appointment and exclusion of contraindications. Patients were assessed three times: before, immediately after, and six months post-treatment, using the International Index of Erectile Function-5 Questionnaire (IIEF-5). Results: The pre-treatment IIEF-5 score in the study group was 12.6 ± 3.9 increased to an average of 18.0 ± 3.4 points after treatment. Six months post-treatment, a further increase was noted to an average score of 18.9 ± 4.1 – statistically significant differences (p <0.05). A negative correlation was observed between the duration of erectile dysfunction and the results before treatment (−0.3526; p <0.05 – average correlation), immediately after (−0.0777; p <0.05 – low correlation), and six months after (−0.5180; p <0.05 – high correlation) the end of treatment. A positive correlation was observed between pre-treatment IIEF-5 scores and results immediately after treatment (0.6113; p <0.05 – high correlation) and six months (0.5207; p < 0.05 – high correlation) after the end of treatment (p <0.05). A negative correlation was observed between the number of shock wave pulses and IIEF-5 scores obtained before (−0.6963; p <0.05 – high correlation), immediately after (−0.5885, p <0.05 – high correlation), and six months after the end of treatment (−0.6884, p <0.05 – high correlation). Conclusions: 1. Low-intense extracorporeal shock wave therapy improves erectile function in patients with erectile dysfunction. 2. Positive effects on erectile function, as assessed by IIEF-5, were observed immediately after treatment and persisted at six-month follow-up. 3. Erectile dysfunction duration negatively affected IIEF-5 scores before, immediately after, and six months post-treatment. 4. Patient age had no impact on IIEF-5 scores at the end of the treatment and at six-month follow-up.