The objective of this study was to evaluate the long-term (9 yr) effect of liquid hog manure (LHM) on (i) the chemical partitioning of Cu in the soil profile and (ii) to evaluate the relationship between Cu and soluble organic C in runoff and drainage water. The site under corn and forage was located in Quebec, Canada on a loamy Aquic Haplorthod with 6% slope. Each plot was equipped to collect surface runoff and drainage water separately throughout the year. The results show that the repeated application of LHM increased the total soil Cu content under both crops. The residual fraction was the most abundant with proportions up to 85% of total Cu. It was followed by the organic fraction. Accumulation of Cu was also found in layers below 20 cm in fractions not readily available to plants but also in labile and moderately labile fractions under both crops. In surface runoff, Cu concentrations were similar under the two cropping systems even if LHM was applied at lower rates under forage than under corn. This result suggests the LHM left at the surface of the soil under forage could be more prone to runoff. Significant correlations were found between Cu and DOC for corn and forage. Similar Cu concentrations in tile-drain water were also found between the two crops suggesting that the vertical macropores usually found under perennial forage production could increase the proportion of Cu reaching the tile drains via preferential water flow. Significant correlations between DOC and Cu for both crops were also found in drainage water. The results indicate that long-term application of LHM induced Cu accumulation in the soil surface but also below the LHM incorporation depth and that DOC interacted with Cu which likely enhanced its mobility.