In　this　paper,　we　consider　a　reactiondiffusion　model　of　plankton　allelopathy　with　nonlocal　delays.　Using　an　iterative　technique,　the　global　stability　of　the　positive　steady　state　and　the　semi-trivial　steady　states　of　the　system　is　investigated　under　some　weaker　conditions　than　those　assumed　in　Tian　et　al.　[C.R.　Tian,　L.　Zhang　and　Z.　Ling,　The　stability　of　a　diffusion　model　of　plankton　allelopathy　with　atio-temporal　delays,　Nonlinear　Anal.　RWA　10　(2009)　20362046].　We　also　show　that　toxic　substances　and　nonlocal　delays　are　harmless　for　the　stability　of　the　positive　steady　state.　Finally,　some　examples　are　presented　to　verify　our　main　results.　©　2010　Elsevier　Ltd.　All　rights　reserved.