Abstract: An adjustable manhole cover support frame that includes a base unit, a top support unit telescopically arranged on the base unit and screw jacks interconnecting the two units permitting selectively adjusting the relative telescopic position of the top unit on the base unit. The base unit has an open ended sleeve projecting upwardly from a flange utilized to secure the base unit to the top end of a manhole vertical conduit. The top support unit has a top annular plate from which depends three cylindrical walls defining a first outer cavity telescopically receiving the sleeve of the base unit and inwardly therefrom a second cavity with holes in the bottom to receive the upper ends of threaded bolts that provide the screw jacks for adjustment.