This research aimed to conduct water quality assessment in the port area covered by the Keelung Port in Keelung City, Taiwan and to determine if spatial variability and tidal variability affect the water quality parameters. This research addresses the gap on the limited work published on the pollutants present and dissolved in the water. Relatively little attention has been given to the study area, where different shipping operations may have considerable impacts on the water quality in the port environment. Based on the standards set by the Taiwan International Ports Corporation (TIPC), pH and DO are within the permissible values. DO was markedly lower during high tide, which was consistent with the findings of other researchers. The concentration of mercury, arsenic, and chromium were all below the detection limits of the measuring equipment used in the research. Water quality is significantly affected by the location of sampling area, whereas the inner port area showed relatively higher level of contamination compared with the measurements taken at the outer port area. Based on the independent samples Mann-Whitney U test conducted, tidal condition does not significantly affect the distribution of measurements of the water quality parameters.