Water is an inevitable aspect of not only humans but all living beings. On the other hand, contamination of water results in many acute and chronic illnesses in humans, and environmental pollution. In this study, the iron oxide particles were synthesized in a simple aqueous-based technique using the seed extract of Syzygium cumini as the source of both reducing and capping agent. These particles show the magnetic character therefore, an external magnetic field was applied to separate the particle from the solution. The kinetic study showed that particles removed 92% of Cd ion in 30 minutes from wastewater. Moreover, this research revealed that the synthesized particles could be a very promising material to remove Cd ion from the wastewater.