Islam Khan Mashadi (fl.  3 May 1635 – c. 3 August 1656) was the Mughal Subahdar of Bengal and later Grand Vizier during the period 1639–1645. His original name was Mir Abdus Salam. He was also served high service in Viceroy of Kabul from 1647 till his death in 1656.

In 1639, soon after the Ahom-Mughal and Arakan-Mughal battles, Islam Khan Mashhadi was recalled to Delhi to assume the post of Wazir (Prime Minister). Prince Shah Shuja succeeded him as the new governor of Bengal. Islam Khan II then became the governor of the Deccan provinces in the year 1646-1647. Islam Khan's success in defeating the Assam impressed the emperor, and he invited Islam Khan back to the capital and made him grand vizier. Afterwards, Shah Jahan wanted to make Saad Ullah Khan the vizier. Islam Khan understood and volunteered himself for the viceroyalty of the Deccan, which Shah Jahan approved. Islam Khan fell ill on his way to the Deccan, and died in 1645. In his will, he divided his property among his sons and brothers, and sent 25 lakhs to the emperor. While the imperial policy was to confiscate all of the property of the jagirdars, on account of his loyalty Shah Jahan chose to overlook this.

Islam Khan Mashadi had six surviving sons at the time of his death.