Three new nanoscopic trigonal prisms, [(tmen)₆Pd₆(H₂L)₃](NO₃)₁₂ (1), [(Meen)₆Pd₆(H₂L)₃](NO₃)₁₂ (2), and [(2,2′‐bipy)₆Pd₆(H₂L)₃](NO₃)₁₂ (3), have been synthesized in excellent yields through single‐step metal–ligand‐coordination‐driven self‐assembly using 5,10,15,20‐tetrakis(3‐pyridyl)porphyrin (H₂L) as a donor and cis‐blocked Pd^II 90° acceptors. These complexes were fully characterized by spectroscopic studies and single‐crystal X‐ray diffraction. All of these barrels quantitatively bind Zn^II ions in the N₄ pockets of the porphyrin walls at room temperature. Their corresponding zinc‐embedded complexes, [(tmen)₆Pd₆(ZnL)₃](NO₃)₁₂ (1 a), [(Meen)₆Pd₆(ZnL)₃](NO₃)₁₂ (2 a), and [(2,2′‐bipy)₆Pd₆(ZnL)₃](NO₃)₁₂ (3 a), were synthesized under ambient conditions by the post‐synthetic binding of Zn^II ions into the H₂N₄ pockets of the porphyrin walls of these complexes. These zinc‐embedded complexes were characterized by electronic absorption, fluorescence emission, ¹H NMR spectroscopy, as well as elemental analysis. Complexes 1–3 exhibited considerable microporosity in their solid state. Complex 1 was an efficient adsorbent for nitrogen gas and EtOH, MeOH, and water vapors.