A guide and safety guard for a table saw, of the type having a table top and a powered saw blade with an exposed saw blade portion projecting above the table top and a movable guide fence positionable on the table top on a far side of the saw blade, has a support rail having opposite ends coupled to support members in a desired spaced relation to the guide fence of the table saw, a guard block mounted by a sleeve portion so as to be slidable on the support rail in axial directions thereon, and rotatable on the support rail so that it can be moved out of and into operative position, wherein the guard block has a height projecting above the table top in the operative position that is greater than the height of the exposed saw blade portion for protecting the hand of the user, and a guard extension fixed to a trailing side of the guard block for protecting the wrist and lower arm area of the user.