Lab-cultured Ulva pertusa were exposed to three selected types of contaminated areas (industry, mariculture and living) and one relatively clean area near Dalian seashore for 1, 3, 5 and 14 days. Relative growth rate, chlorophyll content and activities of two kinds of antioxidant defense enzymes (superoxide dismutase and catalase) were measured and compared with their lab controls at different time points, respectively. No significant change was observed in either relative growth rate or chlorophyll content in 1-day exposed samples, while obvious decreases were observed in relative long-period (3, 7 and 14 days) exposed samples. Antioxidant defense enzymes activities were stimulated to increase after 1-day exposure and decrease after relative long-period exposure. Significant statistical decreases were found in the relative growth rate, chlorophyll content and antioxidant defense enzymes activities of samples from industry pollution area, which indicates a more serious pollution situation in industry area than the other two areas near Dalian seashore. Above results demonstrated the established method would be useful for biological evaluation of multiplex pollution in real situation.