Background: Male infertility remains a significant health concern, and Doppler ultrasonography offers a non-invasive method to assess testicular hemodynamics. This study aimed to evaluate the correlation of testicular artery Doppler parameters (resistive index [RI], peak systolic velocity [PSV], and end-diastolic velocity [EDV]) with semen quality, hormone levels (follicle-stimulating hormone [FSH], luteinizing hormone [LH], testosterone), varicocele degree, and body mass index in men with primary infertility without Y-chromosome microdeletion. Methods: 40 male patients with primary infertility who visited our hospital were included in this study. Secondary data collected included demographic details, hormone levels (FSH, LH, testosterone), sperm analysis, and Doppler ultrasound findings (PSV, EDV, RI) of testicular arteries. Varicocele degree was assessed. Data were analyzed using SPSS 27.0, with descriptive statistics, Shapiro-Wilk tests for normality, Pearson or Spearman correlation tests as appropriate, and significant correlations were further assessed by multivariable linear regression. Results: All patients were diagnosed with varicocele on Doppler ultrasonography, and 25 of 40 participants (62.5%) were azoospermic. Right testicular end-diastolic velocity (EDV) showed a moderate positive correlation with both sperm concentration (r = 0.446, p = 0.004) and motility (r = 0.406, p = 0.009). Right testicular peak systolic velocity (PSV) exhibited a weak positive correlation with age (r = 0.350, p = 0.027) and a weak negative correlation with FSH levels (r = − 0.357, p = 0.024). In regression analysis, right testicular EDV remained significantly associated with sperm concentration (p = 0.017). The median age of the participants was 34.5 years, and their median BMI was 25.9 kg/m². Conclusions: Right testicular EDV was significantly associated with sperm concentration and motility, suggesting that it may serve as a potential independent predictor of sperm quality. Conversely, right testicular PSV, while correlated with age and FSH levels, did not demonstrate independent predictive capability. These findings emphasize the utility of EDV in evaluating male infertility, and as all subjects demonstrated varicocele, they should be interpreted within that clinical context. © The Author(s) 2026.