HTLV-1 is one of the two pathogenic human retroviruses that causes adult T-cell leukemia(ATL), HTLV-1-associated myelopathy(HAM) and HTLV-1 uveitis (HU). Treatment of ATL is still very difficult today, thus search for new agents that target specific molecules are under way. For treatment of HAM and HU, suppression of HTLV-1 replicationappears to be important, as well as prevention of ATL development. Considering the common characteristics as human retroviruses, application of anti-HIV drugs appears to be a reasonable strategy, although it is not yet clinically tested for HTLV-1. Research of agents specific to HTLV-1 viral products needs to be encouraged to develop HTLV-1-specific anti-viral agents.