New indides SrAu{sub 3}In{sub 3} and EuAu{sub 3}In{sub 3} were synthesized by induction melting of the elements in sealed tantalum tubes. Both indides were characterized by X-ray diffraction on powders and single crystals. They crystallize with a new orthorhombic structure type: Pmmn, Z=2, a=455.26(9), b=775.9(2), c=904.9(2) pm, wR2=0.0425, 485 F{sup 2} values for SrAu{sub 3}In{sub 3} and a=454.2(2), b=768.1(6), c=907.3(6) pm, wR2=0.0495, 551 F{sup 2} values for EuAu{sub 3}In{sub 3} with 26 variables for each refinement. The gold and indium atoms build up three-dimensional Au{sub 3}In{sub 3} polyanionic networks, which leave distorted hexagonal channels for the strontium and europium atoms. Within the networks one observes Au2 atoms without Au-Au contacts and gold zig-zag chains (279 pm Au1-Au1 in EuAu{sub 3}In{sub 3}). The Au-In and In-In distances in EuAu{sub 3}In{sub 3} range from 270 to 290 and from 305 to 355 pm. The europium atoms within the distorted hexagonal channels have coordination number 14 (8 Au+6 In). EuAu{sub 3}In{sub 3} shows Curie-Weiss behavior above 50 K with an experimental magnetic moment of 8.1(1) {mu}B/Eu atom. {sup 151}Eu Moessbauer spectra show a single signal at {delta}=-11.31(1) mm/s, compatible with divalent europium. No magnetic ordering was detected down to 3 K. - Graphical abstract: The three-dimensional Au{sub 3}In{sub 3} network in SrAu{sub 3}In{sub 3}.