According to recent literature, there is a limited amount of data about the correlation of vitamin 25(OH)D, potassium (K), oxidative stress parameters, and other biomarkers with dyslipidemia, which is an established risk factor for cardiovascular diseases (CVDs). This study aims to investigate the correlation of lipid profile and atheromatic index TC/HDL with several biomarkers and oxidative stress parameters. A total of 102 volunteers, 67 with atheromatic index TC/HDL > 3.5 (Group A) and 35 with TC/HDL < 3.5 (Group B), aged from 26 to 78 years, participated in this study. Serum levels of triglycerides (TG), total cholesterol (TC), low- and high-density lipoproteins (LDL and HDL), vitamin 25(OH)D [25(OH)D], potassium (K), sodium (Na), lactose dehydrogenase (LDH), liver enzymes including serum glutamic oxaloacetic and glutamic pyruvic transaminases (SGOT and SGPT), gamma-glutamyl transferase (γ-GT), and alkaline phosphatase (ALP) were analyzed using standard photometric methods. Oxidative stress parameters such as reactive oxygen species (ROS) were detected with fluorometric methods, whereas total oxidative (TOS) and antioxidative status (TAS) were measured with spectrophotometric methods. According to the results, negative correlations of HDL (r = −0.593) and 25(OH)D (r = −0.340) and K (r = −0.220) were found, and positive expected correlations of LDL (r = 0.731), TC (r = 0.663), and TG (r = 0.584) with atheromatic index in the total studied sample were found. In conclusion, patients with a dyslipidemic profile should frequently check not only their lipid profile but also other biomarkers such as 25(OH)D, potassium, and oxidative stress markers to predict dyslipidemia and avoid subsequent disorders.