Abstract: We studied the preparation and performance of the tartaric acid modified electrodes, and found the conditions for determining trace copper (Ⅱ). These electrodes have good reproducibilily and the sensitivity is increased by one order of magnitude. There is a good linear relationship between peak height and concentration in the range of 1 to 20 ng/mLof Cu(Ⅱ). At the concentration of 10ng/mL of Cu(Ⅱ), the variation coefficient of six parallel determinations was 1.6%. Moreover, the reaction mechanism of Cu(Ⅱ) at the tartaric acid modified electrodes is discussed. The modified electrodes can increase the number of activated sites, and promote the exchange of electrons, so that both the enrichment efficiency and sensitivity are raised. The stripping process of copper at the modified electrodes is the same as that at glassy carbon electrodes.