China’s strategic position in the South China Sea dispute has created lots of controversy, particularly with the claimants. The activities done by China have triggered heightened tensions especially with Vietnam as one of the biggest claimants in the disputed sea. China did oil drilling in the disputed water with Vietnam and attacked oil exploration vessel which operates in the Vietnamese ZEE as a part of the South China Sea water. Those examples of Beijing actions have made Hanoi worries upon their claims in the South China Sea. In 2009 Vietnam released Defense White Paper which contained the defense policy of Vietnam as well as Vietnam’s concerns upon the South China Sea dispute. Vietnam has implemented its defense policy in the field of economy, military, politics, and technology. The implementation of Vietnam defense policy is a part of Vietnam’s action in encountering China’s strategic position in the disputed waterways. In general, this writing aimed to analyze the particular issues by using the theories of defensive realism and defense policy to answer the research question on how Vietnam implemented its defense policy in encountering China’s strategic position in the South China Sea dispute.