One of the six major meteoric lakes in the world, Lake Bosomtwe, is of great ecological significance for Ghanaians and the scientific community, most importantly for agricultural and human consumption. Water samples (n = 30) were collected to analyze the hydrogeochemical characteristics and water quality of the lake. Statistical methods including correlation, principal component, cluster analysis, Gibbs ratio, and the Piper–Trilinear diagram were used to analyze parameters. The Water Quality Index revealed that the lake water is not suitable for human consumption because measured pH, temperature, total dissolved solids, color, and bicarbonate exceeded their respective thresholds on all occasions. The calculated sodium absorption ratio (13.7–14.8) and soluble sodium percentage (94.43–95.43%) showed that the lake is not appropriate for irrigation as they exceeded their respective limit of 2 and 60%. The Gibbs ratio revealed that rock–water interaction is the underlying mechanism for water evolution. The Piper–Trilinear diagram revealed that alkalies earth and weak acids dominate the water chemistry of the lake. The dominant cation is sodium (82.22%), while the dominant anion is bicarbonate (79.39%). Five monitoring stations were identified, and the water quality was influenced by diverse anthropogenic and natural sources. The findings will provide a reference for policymakers and decision-makers at Lake Bosomtwe.