An acidic mining lake located in Can, Turkey was investigated to assess its water quality status and potential risk for environment. Morphological studies and water quality sampling were conducted to determine vertical and areal distributions of numerous water quality criteria and to assess the general status of the lake. The results revealed that the lake had an average pH of 2.28 and an average electrical conductivity value of 5925 microS/cm. The dissolved oxygen ranged between 0.83 and 6.45 mg/L and demonstrated a significant vertical profile. Sulfate was found to be the dominant anion with an average level of 5912.5 mg/L depicting the extent of pyrite oxidation. Similarly, aluminum, iron and manganese levels were extremely high with averages of 290155, 172344 and 91342 microg/L, respectively. With these levels, the lake is classified to be a Class 4 water resource according to pertinent regulations and is in need of immediate action for rehabilitation.