Abstract: A guide device for a turbine with a guide-blade carrier installed in a turbine housing, preferably the housing of a steam turbine, and equipped with guide blades, includes positioning elements for positioning and fastening the guide blades to the guide-blade carrier and for ensuring a specific installation position of the guide blades. In order to simplify the production of the guide device, two halves of a guide-blade ring divided in the region of a parting plane of the turbine housing serve as the positioning elements. Radially extending profile holes for inserting a guide-blade root of each guide blade are formed in the guide-blade ring. At least one first holding element is preferably releasable and in each case fixes the guide-blade root to the guide-blade ring. At least one second holding element retains each of the two halves of the guide-blade ring on the guide-blade carrier.