We report the complete genome sequence of a new avastrovirus of goose-origin (FLX). The 7299-nt-long genome consisted of three overlapping open reading frames (ORFs) that were in different reading frames. Pairwise comparisons showed that the FLX genome was 59% identical to its closest relatives and that the levels of amino acid identity shared by FLX with other astroviruses did not exceed 54% in ORF1a, 66% in ORF1b, and 50% in ORF2, respectively. Phylogenetic analysis based on the amino acid sequence of the full-length ORF2 demonstrated that FLX was highly divergent from all other avastroviruses. At the amino acid level the complete capsid region of FLX shared genetic distances of 0.574-0.719 with three official avastrovirus species, suggesting that it can be classified as a member of a novel species in the genus Avastrovirus.