MSPI may refer to:
MSPI (nerve agent), an irreversible acetylcholinesterase inhibitor mini-SPI (mSPI), a synchronous serial communication protocol` MspI, a restriction enzyme used in various methods such as the HELP assay Milk soy protein intolerance, a combination allergic intolerance to proteins in both dairy and soy milk; see Milk allergy#Cross-reactivity with soy