Traditionally, environmental monitoring has been used to assess water quality for domestic supply or industrial use. However, this method only reflects the momentary condition and provides poor predictions levels and effects on ecosystems. In this research, biomonitoring- a better method was applied to study the relationships between environmental and biological effects for a reliable risk assessment of aquatic pollution in Saigon River, South Vietnam. This study involves the use of organisms (snake head fish and spinach) from Saigon river as indicators to reflect overall ecological integrity and holistic measure of environmental conditions. This also provides assessment of the enviromental risks to the communities and information to local authorities for managing polution from industrial and agricultural sources.