Tunable fluorescence emission materials play a critical role in many fields such as biology and chemistry. With respect to metallo‐supramolecular assemblies, the construction of 3D tunable‐fluorescent supramolecular assemblies with 2,2′:6′,2″‐terpyridine (tpy) is still in its infancy. In this study, two luminous 3D supramolecular prisms self‐assembled with two terpyridine‐based tetraphenylethylene (TPE) ligands and metal Zn(II) are prepared, and the influence of hydrophobic alkyl chains on tunable fluorescence is further explored. By exploiting hydrophobic properties, the prism SA exhibits tunable visible‐light emission in the molecular‐aggregated state. Moreover, SA forms left‐hand and right‐hand helical nanofibers by hierarchical self‐assembly. However, the prism SB without hydrophobic chains does not exhibit tunable fluorescence emission, and only random spherical aggregates after hierarchical self‐assembly are formed. This study can aid to further strengthen the understanding about the effect of hydrophobic segments on photophysical properties and hierarchical self‐assembly of discrete supramolecular architectures.