Reproductive health is one of the important indicators of life quality. Today, sexual dysfunctions such as low libido, erectile dysfunction, premature ejaculation, delayed or inhibited orgasm are becoming increasingly common in male individuals. Among the supportive treatments for the treatment of sexual dysfunctions, phyto and ethno therapies are gaining popularity in today's world. Fucus vesiculosus (FV) and Laminaria digitata (LD) have antioxidant, anti-tumor, anticoagulant, anti-obesity, anti-inflammatory, antiviral and antibacterial activities. The aim of this study was to investigate the effects of FV and LD extracts on protein levels of phosphodiesterase type 5 (p-PDE5), cyclic guanosine monophosphate (cGMP), endothelial nitric oxide synthase (eNOS) and endothelial-1 (ET-1) in prostate and seminal vesicular tissues. A total of 21 male 12-week-old Sprague-Dawley rats were used in the study. The rats were divided into three groups. 1) Control group, 2) FV group and 3) LD group. FV and LD were administered daily for 52 days via gastric gavage at a dose of 300 mg/kg BW. Among FV and LD groups, the prostate tissues, p-PDE5 (P<0.01), cGMP (P<0.001) and eNOS (P<0.05) levels were higher than controls while ET-1 (P<0.01) levels had lower protein levels. In seminal vesicle tissues, p-PDE5 (P<0.001) and eNOS (P<0.001) levels were higher than controls and cGMP (P<0.01) levels were higher only in the LD group. The level of seminal vesicle ET-1 (P<0.001) decreased similarly to prostate tissue. In conclusion, it is thought that FV and LD extracts may have beneficial effects on sexual dysfunctions by regulating p-PDE5, cGMP and eNOS, ET-1 signaling pathways.