Embodiments of apparatuses, methods, and systems for input/output translation lookaside buffer (IOTLB) prefetching are described. In an embodiment, an apparatus includes a bridge, an input/output memory management unit (IOMMU), and an IOTLB prefetch unit. The bridge is between an input/output (I/O) side of a system and a memory side of the system. The I/O side is to include an interconnect on which a zero-length transaction is to be initiated by an I/O device. The zero-length transaction is to include an I/O-side memory address. The IOMMU includes address translation hardware and an IOTLB. The address translation hardware is to generate a translation of the I/O-side memory address to a memory-side memory address. The translation is to be stored in the IOTLB. The IOTLB prefetch control unit includes prefetch control logic to cause the apparatus to, in response to determining that the memory-side address is inaccessible, emulate completion of the zero-length transaction.