In this paper, final consonant clusters of New Persian are compared statistically to those of Middle Persian from the viewpoint of their conformity to Sonority Sequencing Constraint (=SSC). In this regard, since Middle Persian is an extinct language, it was first necessary to hypothesize a syllabification pattern for this language according to some phonological universals. Then, for each type of sonority profile, or each combination of sonority classes (e.g. liquid+nasal or nasal+stop) in both Middle and New Persian, the frequency is counted at four levels: types (clusters with different segmental structures), tokens (clusters in codas of non-identical syllables), repetition in all codas (no matter the syllables are identical or different) and repetition in word-final positions; and afterwards, these frequencies are compared for the two languages. Analyses of inferential statistics indicate that, at all the four above-mentioned levels, the general statistical tendency in satisfying the Sonority Sequencing Constraint is the same for final consonant clusters of both Middle and New Persian: clusters which satisfy the SSC are the most frequent, and the least frequent clusters are those with unchanged degree of sonority, clusters violating the SSC are located in between. In addition, at the levels of types and tokens, the ‘distribution’ of clusters among these three classes of the overall sonority envelope (~SSC, +SSC, 0-SSC) follows the same pattern in Middle and New Persian.