Technologies for USB controller state integrity protection with trusted I/O are disclosed. A computing device includes an I/O controller, a channel identifier filter, and a memory. The I/O controller generates a memory access to controller state data in a scratchpad buffer in the memory. The memory access includes a channel identifier associated with the I/O controller. The channel identifier filter determines whether a memory address of the memory access is included in a range of a processor reserved memory region associated with the channel identifier. A processor of the computing device may copy the controller state data to a memory buffer outside of the processor reserved memory region. The computing device may reserve an isolated memory region in the memory that includes the processor reserved memory region. Secure routing hardware of the computing device may control access to the isolated memory region. Other embodiments are described and claimed.