Two　aldehyde　group　functionalized　iridium(III)　complexes　were　synthesized　and　characterized.　The　electronic　absorption,　emission　and　transient　emission　spectra　were　studied.　The　crystal　structure　of　one　of　the　complexes　has　been　determined.　Their　interaction　with　homocysteine　(Hcy)　was　investigated　by　UV-vis　absorption,　photoluminescence　(PL),　H-1　NMR　and　mass　spectroscopies.　The　photoluminesce　of　the　complexes　was　enhanced　significantly　after　addition　of　Hcy　due　to　the　formation　of　thiazide　product,　while　there　are　no　obvious　changes　in　the　emission　spectra　after　addition　of　cysteine　(Cys)　and　glutathione　(GSH).　These　probes　can　be　used　for　discriminating　Hcy　from　Cys　and　GSH　efficiently.　(C)　2019　Elsevier　B.V.　All　rights　reserved.