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Partitioning to suspended sediments plays an important role in controlling metal speciation in natural waters. In order to model both dissolved and particulate forms of metals, it is essential to determine possible relationships between partition coefficient (KD) and various water quality variables. This paper examines temporal variability in particulate and dissolved metals (Al, Fe, Mn, Cu, and Zn) collected from a rural stream (NW Spain) during three years under baseflow and runoff events conditions, and investigates the role of pH, suspended sediments (SS) and dissolved organic carbon (DOC) on KD of these metals. The mean concentrations of metals during events were much higher than those in baseflow (except MnD and CuD), but particulate metals were always predominant. Metal concentrations did not exhibit a seasonal pattern. Generally, a similar pattern of metals to discharge was seen for both hydrological conditions, although different metal-discharge relationships were observed depending on the type and form of the metal: negative for FeD and MnD, no relation for AlD, CuD, and ZnD, and positive correlation for all particulate metals (except for CuP and ZnP in baseflow). Partitioning results showed that SS and DOC were the main factors in controlling KD of all metals during events (except for Fe) as well as KD of Al under baseflow. SS play the most important role on KD of Cu and Zn in baseflow, and DOC on KD of Fe (regardless of the discharge regime). For all the above-mentioned findings, this study demonstrates the need to consider hydrological changes when we analyze geochemical factors affecting metal concentrations, even in relatively unpolluted environments.