Viruses are obligate intracellular pathogens that depend on host factors to complete their infection cycle. Very little is known of which plant factors are required for successful Tomato spotted wilt orthotospovirus (TSWV) infection. The viral ribonucleoprotein (RNP) fraction from TSWV infected Nicotiana benthamiana plants was purified and its protein composition was analysed by proteomics by mass spectrometry to identify host proteins that co-purify with viral RNPs. Related, we expressed a TSWV replicon system in a non-host system, Bakers’ yeast (Saccharomyces cerevisiae), and purified as well the RNP fraction from yeast. Comparative proteomics was used to find common enriched proteins observed in both yeast and plant RNP fractions.