In this work, the influence of the substrate on the formation and air stability of metalorganic oligomers on Au(111) and Ag(111) from photoactive I-BOPHY-I molecules has been investigated. A multi-technique analysis combining STM and XPS, and supported by DFT theoretical calculations, allows for a comprehensive characterization from the structural and chemical points of view. On Au(111), typically being the most inert surface, the intact I-BOPHY-I molecules are mostly arranged into a linear self-assembly although a minority phase formed by BOPHY-based dimers is also observed at RT. At 370 K, the molecules are completely dehalogenated and form extended compact islands of chains through surface adatoms. On Ag(111), most molecules undergo a complete dehalogenation at the surface already at RT, resulting in the formation of BOPHY-based oligomers at this temperature. When the temperature is increased to 370 K, longer chains are obtained on this surface as compared to the Au(111) one. Additionally, the air stability of the oligomers has been tested, as a first step toward applications, being more stable on Au(111) than on Ag(111), where a transformation of metal-organic into ether-bridged BOPHY-based oligomers occurs. This research highlights the opportunity to develop low-dimensional photoactive materials that are promising for practical applications and the crucial role that the supporting substrates can play not only in the formation of the nanostructures but also in their air stability and integrity.