We propose a digital rights management (DRM) sys-tem based on mobile agent to protect the copyrights of content providers. In the system, the content provider creates a time lim-ited blackbox out of an original agent and dispatches it to the user end to enforce DRM functions. The blackbox is an agent that can resist the attacks from the malicious user in a certain time interval. Owing to digital rights redistribution support, the user whose rights belong to redistribution category can transfer his rights to other users. Moreover, by introducing public key infrastructure (PKI) and certificate authority (CA) role, the security of the ses-sion can be ensured. An analysis of system security and perform-ance and a comparison with traditional DRM system is given. We propose a digital rights management (DRM) sys-tem based on mobile agent to protect the copyrights of content providers. In the system, the content provider creates a time lim-ited blackbox out of an original agent and dispatches it to the user end To enforce DRM functions. The blackbox is an agent that can resist the attacks from the malicious user in a certain time interval. Owing to digital rights redistribution support, the user whose rights belong to redistribution category, can transfer his rights to other users. Moreover, by introducing public key infrastructure (PKI) and certificate authority (CA) role, the security of the ses-sion can be ensured. An analysis of system security and perform-ance and a comparison with traditional DRM system is given.