The usefulness of fluorescence parameters as drought tolerance selection criteria for winter bread wheat in the highlands of Iran was studied. A population of 142 recombinant inbred lines, derived from a cross between two common wheat varieties, Azar2 (winter type) and 87Zhong291 (facultative type), was used to analyze the correlation between grain yield and chlorophyll fluorescence parameters at the grain-filling stage under drought stress and supplementary irrigation conditions during 2006–2007 and 2007–2008 seasons at Maragheh experiment station of the Dryland Agricultural Research Institute (DARI) using a RCBD with three replications. The results showed significant differences among the lines in the grain yield and all fluorescence parameters under rainfed and irrigation conditions. The values of chlorophyll content, F 0, F m, F v, F v/F m, LWP, YPEC, NPQ, and PI in the drought-tolerant genotypes were significantly higher than those in drought-sensitive genotypes under drought stress. Significant differences were observed between slope coefficients under drought, but not under supplementary irrigation conditions except NPQ (P = 5%). It was concluded that chlorophyll content, F 0, F m, F v, F v/F m, LWP, YPEC, NPQ, and PI could be used as additional indicators in screening wheat germplasm for drought tolerance.