The fall armyworm, Spodoptera frugiperda is an invasive pest in Africa in 2016 and in Senegal in 2017. This species is very voracious and polyphagous. During its development cycle, the larva can move from one refuge plant to another. Thus, it would be interesting to inventory new host plants of Spodoptera frugiperda in Senegal for a better management of the pest. It is in this context that surveys were carried out on crops and spontaneous vegetation inside and outside the fields, in one year, during the rainy and dry seasons in the Groundnut Basin, Casamance and Niayes. A total of 22 host plants divided into 11 families of which the most represented are the Poaceae (50%) were recorded. Among the species, Zea mays is the most attacked, followed by Sorghum bicolor, Digitaria horizontalis and Capsicum annum which are accessory hosts. According to the results obtained, S. frugiperda preferentially consumes foliage. This study revealed the existence of 4 new host plants inventoried in Senegal, namely Eragrostis tremula and Pennisetum violaceum in the Groundnut Basin, Andropogon gayanus and Commelina forskalaei in Casamance. All these species are weeds belonging to the Poaceae family and seem to play a major role in maintaining pest populations. However, species such as Arachis hypogaea (Fabaceae) in the Groundnut Basin and Casamance; Mitracarpus villosus and Spermacoce chaetocephala (Rubiaceae) in Casamance have been suspected to be hosts of S. frugiperda in Senegal. It should be noted that the latter has never been reported.