Psoriasis is an inflammatory dermatosis with a complex pathogenesis, significantly impacting the quality of life of patients. The role of oxidative stress and gut microbiota in the pathogenesis of this disease is increasingly studied, appearing to underlie the comorbidities associated with this condition. We present the first prospective observational study conducted in Romania evaluating the interrelationship between gut microbiota and hematological, inflammatory, biochemical, and oxidative stress parameters in treatment-naïve psoriasis patients. Significant differences were observed in terms of microbiota composition, with lower levels of Firmicutes and Enterobacteriaceae in the psoriasis group compared to the control group. Moreover, a negative correlation was found between the serum triglyceride levels in patients with psoriasis and the Enterobacteriaceae family (p = 0.018, r = −0.722), and a positive correlation was found between the serum glucose levels and the Firmicutes/Bacteroides ratio (p = 0.03, r = 0.682). Regarding the oxidant–antioxidant status, a significant correlation was found between the FORT level and Lactobacillus (p = 0.034, r = 0.669). Lastly, the Firmicutes level negatively correlated with the DLQI level, independent of the clinical severity of the disease (p = 0.02, r = −0.685). In conclusion, even though the number of included patients is small, these results may serve as a starting point for future research into the involvement of the microbiota–inflammation–oxidative stress axis in psoriasis development.