The Translocase of the Outer Membrane (TOM) complex is the main entry gate into the mitochondria for most precursor proteins. These proteins have mitochondrial targeting sequences that contain information about their distribution throughout the organelle. The TOM core complex is a heterodimer formed by Tom40, the translocation pore, Tom22, the main presequence receptor, and three small Tom subunits. However, two other receptor subunits, Tom20 and Tom70, are associated with the complex and have been a difficult target in structural biology. In this study we obtained the high-resolution structure of the TOM core complex from Neurospora crassa, obtained through Cryo-EM Single Particle Analysis, as well as a lower-resolution structure of the TOM core complex in association with Tom20. Furthermore, we present the multiple subcomplexes formed by the TOM subunits obtained by native mass spectrometry, bringing insight to the interaction of Tom20 and Tom70 with the TOM core complex. We propose that Tom20 is the dynamic gatekeeper guiding precursor proteins in the first steps of translocation, as it guides them into the Tom40 pores. Our study sheds new light into the so far elusive TOM holo complex and offers an integral translocation mechanism.