The purpose of the present study is to assess the levels of nitrate (NO3-) and phosphate (PO43-)ions and selected metals (Mg, Ca, Zn and Cu) in water samples collected intwo seasons, April 15 to 18/2018 (dry season) and June 18 to21/2018,(wet season) from three different sites of SerentaRiver,northern west ofTigray, Ethiopia. Standard methods were used for the assessment of ions and metals. Nitrate and phosphate contents of the water samples were analyzed using photometry whereas the metals were analyzed using inductively coupled plasma optical emission spectroscopy. The validity of the method of the analysis was confirmed by recovery test and the result was in the range (92.7 to 98.4). Statistical analysis was performed to check whether the difference is statistically significant or not. The highest and lowest mean concentration of nitrate was found to be 2.167 ±0.158 and 1.067 ± 0.153 mg/L in the dry season samples and 6.833 ± 0.158 and 1.067 ± 0.115 mg/L in the wet season samples respectively. Whereas the highest and lowest mean concentration of PO43- was 1.057 ± 0.153 and 0.293 ± 0.006 mg/L in the dry season samples and0.490± 0.060 and 0.343 ±0.021 mg/L in the wet season samples respectively. Based on the statistical analysis the highest concentration of the metals magnesium, calcium and copper was found to be 6.350, 17.725 and 0.03 mg/L in the wet season samples respectively. But highest concentration of zinc (0.063mg/L) was found in the dry season sample. The metals (Mg and Ca) and the anions (nitrate and phosphate) were detected in all samples.But zinc metal was not detectedin site-3 of both dry and wet samples. The mean concentration of copper in site-3 of the dry season sample was found below the method detection limit. Even though the concentrations of nitrate and phosphate ions and the metals (Mg, Ca, Zn and Cu) are below the World Health Organization recommended values, there was a seasonal fluctuation in their concentrations in water. This variation may be due to human activities and natural processes. Keywords: Nitrate, Phosphate, Metals, Synthetic fertilizer, Serenta, Water pollution