Plant fibrillins are a well‐conserved protein family found in the plastids of all photosynthetic organisms, where they perform a wide range of functions. A number of these proteins have been suggested to be involved in the maintenance of thylakoids and the formation of plastoglobules, preventing their coalescence and favoring their clustering via an as‐yet unidentified cross‐linking mechanism. In this work we show that two members of this group, namely fibrillin 1a and 1b, interact with each other via a head‐to‐tail mechanism, thus raising the possibility that they form homo‐ or hetero‐oligomers and providing a mechanism to understand the function of these proteins.