The prōtasēkrētis (Greek: πρωτασηκρῆτις), also found as prōtoasēkrētis (πρωτοασηκρῆτις) and Latinized as protasecretis or protoasecretis, was a senior official in the Byzantinebureaucracy. The title means "first asēkrētis", illustrating his position as the head of the order of the asēkrētis, the senior class of imperial notaries.
His subordinates included not only the asēkrētis, but also the inferior class of the imperial notarioi, under their head, the prōtonotarios, as well as the official known as dekanos, placed "in charge of the imperial papers" according to the De Ceremoniis of Emperor Constantine VII Porphyrogenitus (r. 913–959). The prōtasēkrētis seems also to have been in charge of preparing the imperial chrysobulls. After 1106, however, he was moved from the chancery and assumed judicial duties, heading one of the highest courts of the Byzantine Empire, along with the eparchos, the megas droungarios tēs viglas, the dikaiodotēs, the koiaistōr, the epi tōn kriseōn, and the katholikos, who headed the court for fiscal affairs (dēmosiaka pragmata). Although the class of the asēkrētis is not attested after the 12th century, the post of prōtasēkrētis survived into the Palaiologan period.