Ivan Mikhailovich Viskovatiy (Viskovatov) (; died 1570 in Moscow) was a Russian diplomat and head of the Posolsky Prikaz (foreign ministry).
Viskovatiy rose to the rank of dyak by 1549 during Ivan the Terrible's intensive organizational activities. Together with Alexei Adashev, he managed Russia's foreign relations during the 1550s. Historians believe that the Posolsky Prikaz was formally established in 1556, owing in part to the efforts of Viskovatiy. He was also the one to inventory the archives of the ministry of foreign affairs. In 1561, Viskovatiy was appointed the keeper of the seal, combining the custody of the seal of the Russian state with the diplomatic department. This tradition would remain in place until the 17th century. As keeper of the seal, Viskovatiy was also made a member of the Boyar Duma.
When Ivan the Terrible became seriously ill in 1553, Viskovatiy was among the first to swear allegiance to the tsar's infant son, Dmitry Ivanovich, opposing the faction supporting Vladimir of Staritsa. In 1554, Viskovatiy was appointed a member of the boyar investigation committee regarding Prince Semeon Rostovsky's treason. During the 1553–1554 church councils, Viskovatiy accused the priest Sylvester and others in disputes over religious doctrine and the canonicity of newly painted icons. The council rejected his accusations and imposed a three-year penance on Viskovatiy. In 1563, Viskovatiy went on a diplomatic mission to Denmark to hold negotiations on Livonian affairs during the build-up to the Northern Seven Years' War. In 1566, Viskovatiy took part in the Zemsky Sobor.
Viskovatiy managed to escape the tsar's disgrace during the 1560s. In 1570, he was accused of intending to give Novgorod to the Polish king and Astrakhan and Kazan to the Turkish sultan. He was publicly executed in Moscow in 1570 during the oprichnina terror. His wife was sent to a monastery.