We re‐diagnoseRhysacephalaBenson, 1954, a genus of xiphydriid woodwasps confined to eastern mainland Australia, Tasmania and Lord Howe Island.Rhysacephala leai(Forsius, 1927), including the first description of the female,Rhysacephala obtusiventris(Rohwer, 1918), andRhysacephala wilsoniBenson, 1954 are redescribed. Six new species from eastern Australia are described:Rhysacephala amplipretarsusJennings, Parslow & Macdonald,sp. nov.,Rhysacephala fulvaJennings, Parslow & Macdonald,sp. nov.,Rhysacephala impensaJennings, Parslow & Macdonald,sp. nov.,Rhysacephala monteithiJennings, Parslow & Macdonald,sp. nov.,Rhysacephala phalarosJennings, Parslow & Macdonald,sp. nov.andRhysacephala tenebrilataJennings, Parslow & Macdonald,sp. nov.A monotypic genus,AustroxiphydaJennings, Macdonald, Schiff & Parslow,gen. nov., is established and includesAustroxiphyda lasalleiJennings, Macdonald, Schiff & Parslow,sp. nov.Keys to identify the 12 Australian species of Xiphydriinae are provided.