Generally, metal–organic frameworks (MOFs) are made up from kinds of repeating microporous structure. Here, a series of Eu3+ ions activated terephthalate‐based lanthanum–organic frameworks (La–MOFs) was synthesized by a hydrothermal reaction. By controlling the reaction time, we obtained some unique brick‐shaped La–MOFs in a micron scale size range, and these La–MOFs showed tunable mesoporous and macroporous architectures. It is speculated that the change in the composition and structure of building units results in the formation of this mesoporous and macroporous heterogeneous architectures. Powder X‐ray diffraction patterns and Eu3+ luminescence behavior support the speculation.