The experienced 32-year-old, who joins on a free transfer, has signed a two-year deal with the Iron.
The former Notts County and Barnet player made 35 appearances for Blackpool last season.
Bishop is Scunthorpe's second signing of the summer, following the acquisition of winger Jennison Myrie-Williams from Port Vale last week.
Newly-promoted League One side Scunthorpe United have signed midfielder Neal Bishop from Blackpool.