The mitochondrial NADH:ubiquinone oxidoreductase, or complex I, is composed of a hydrophobic arm comprising the P module and a hydrophilic arm comprising the N and Q modules. The assembly of complex I is well characterized in humans and catalyzed by a series of assembly factors that join the Q, P, and N modules sequentially. The complex I of protists and plants contains additional ancestral features, like the ferredoxin bridge that connects the matrix and the membrane arms and the  carbonic anhydrase domain, which raises the question of their assembly. In this work, a strain where the assembly factor NDUFAF3 has been tagged with a 3xFLAG at the C-terminal extremity has been investigated in the green microalga Chlamydomonas reinhardtii. Like its human homolog, NDUFAF3 interacts strongly with the classical subunits of the Q and P modules, but also with the  carbonic anhydrase domain and C1-FDX, one of the subunits of the ferredoxin bridge. The predicted structural positioning of NDUFAF3 within the Q module suggests a role in the formation of the ferredoxin bridge. In contrast, subunits of the N module are only loosely associated with NDUFAF3. We further demonstrate that the N module is attached at a later stage of assembly, suggesting that Chlamydomonas complex I assembles in a human-like pathway. This contrasts with the situation in Angiosperms where the N and the Q modules are attached together before anchoring to the P module. Altogether, these results highlight a conserved and ancestral role of NDUFAF3 in complex I manufacture.