In　this　study,　a　robust　interval-based　minimax-regret　analysis　(RIMA)　method　is　developed　and　applied　to　the　identification　of　optimal　water-resources-allocation　strategies　under　uncertainty.　The　developed　RIMA　approach　can　address　uncertainties　with　multiple　presentations.　Moreover.　it　can　be　used　for　analyzing　all　possible　scenarios　associated　with　different　system　costs/benefits　and　risk　levels　without　making　assumptions　on　probabilistic　distributions　for　random　variables.　In　its　solution　process,　an　interval-element　cost/benefit　matrix　can　be　transformed　into　an　interval-element　regret　matrix,　such　that　the　decision　makers　can　identify　desired　strategies　based　on　inexact　minimax　regret　(IMMR)　criterion.　Moreover,　the　fuzzy　decision　space　is　delimited　into　a　more　robust　one　through　dimensional　enlargement　of　the　original　fuzzy　constraints.　The　developed　method　is　applied　to　a　case　study　of　planning　water　resources　allocation　under　uncertainty.　The　results　indicate　that　reasonable　solutions　have　been　generated.　They　can　help　decision　makers　identify　desired　strategies　for　water-resources　allocation　with　a　compromise　between　maximized　system　benefit　and　minimized　system-failure　risk.　(C)　2009　Elsevier　B.V.　All　rights　reserved.