The overall goal of this thesis was to determine whether envelope-free Ebola virus (EBOV) nucleocapsids could be isolated. We identified novel structures from EBOV infected cells that we have termed “proto-nucleocapsids”. These proto-nucleocapsids were ~30.5 nm in diameter and single particle image analysis revealed a hollow structure with small lobes, attributed to individual NP molecules. In addition, no large external protuberances on this structure were observed. As such, we hypothesize that the proto-nucleocapsids are the inner NP-RNA layer of the EBOV nucleocapsid. Expression of EBOV NP, VP24, VP30, VP35, and VP40 followed by density gradient ultracentrifugation of cell lysates enabled the isolation of novel nucleocapsid-like particles. These particles had a similar diameter to the EBOV nucleocapsid, but had a slightly larger helical pitch. Characterization of the nucleocapsid-like particles under various conditions demonstrated that the overall integrity of the helical structure was maintained, although a wide range of helical condensation was observed.