The title complex, [Ba(L1)(μ1,2-ClO4)]2(ClO4)2 (where L1 = 5,17-dihydroxy-3,7,15,19,25,26-hexa-azatricyclo(19.3.1.19,13)hexacosa-1(25),2,7,9(26),10,12,14,19,21,23-decaene), was synthesised by a Schiff base condensation of 2,6-diformylpyridine with 1,3-diaminopropan-2-ol in dry methanol using barium(II) as template ion. The complex was characterised by IR, 1H NMR, mass spectrometry, elemental analysis and X-ray crystallography. The structure was solved in the triclinic space group P $$ {\bar{\text{1}}} $$ with a = 8.4587(9), b = 8.7360(9), c = 17.7722(19) A, α = 79.786(2), β = 88.780(2), γ = 83.048(2)°, V = 1283.0(2) A3, Z = 1 and R1 = 0.0433. The macrocycle is folded and the complex dimerises via perchlorate anions which bridge the barium ions, and this interaction is supported by hydrogen bonding between neighbouring alcohol groups. The dimers are further linked into chains via intermolecular O–H···OClO3 hydrogen bonds. An 11-coordinate Ba(II) macrocyclic dimer linked by bridging perchlorate anions and hydrogen bonds.