Purpose: The Ni-base superalloy GTD-111 gains its appropriate microstructure and high temperature strengththrough precipitation hardening mechanism. Because of their service condition, tensile properties of the alloyhave strong influence on stability and life of the blades.Design/methodology/approach: Tensile fracture mechanisms of the cast and heat treated superalloy werestudied over a wide range of temperatures from 25 to 950°C with a constant strain rate of 10-4s-1. The presentpaper provides structural and fractography evidence by means of scanning electron microscopy at differenttemperatures for the superalloy GTD-111.Findings: The variation in alloy ductility was found to correlate well with the fractography results of the tensiletested specimens. Transgranular and intergranular fracture with fine dimples, cleavage facets and a combinationof them were shown in the fractographs.Research limitations/implications: Although tensile properties alone are important for the alloy, it is suggestedfor future research to work on the simultaneous effects of tension and fatigue on the fracture mechanisms.Originality/value: It was cleared that different fracture mechanisms operate in different temperature ranges;while transgranular dimple fracture was dominant at 650°C, the dominant fracture mechanism at roomtemperature was intergranular.