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Introduction Considering the lack of food in the world, increasing the production of rice is one of the demands of the global market and one of the important goals of many countries producing this crop plant. The final performance of each organism is affected by the genotypic potential, the environmental effects and the interaction between genotype and environment. The interaction of genotype and environment causes that different genotypes do not have the same reaction under different environmental conditions. Genotypes that can produce higher yields in different regions or under different environmental conditions and maintain their performance stability are considered as successful genotypes. In this study, nine promising rice lines originating from the Hashemi variety, along with two varieties Hashemi and Gilaneh, were evaluated for grain yield in two regions during two years. The objective of this study was to evaluate the stability of the studied lines and introduce the most stable ones in order to introduce the new varieties. Materials and methods The plant materials of this experiment were nine promising rice lines originating from the Hashemi variety, as a Iranian local variety with good quality, along with two varieties Hashemi and Gilaneh as control varieties. The experiment was conducted in a randomized complete block design with four replications in two regions, Rice Research Institute of Iran (Guilan province, Iran) and Chaparsar Research Station (Mazandaran province, Iran), in two years, 2017 and 2018. The studied traits included grain yield, days to 50% flowering, head rice percentage, milling efficiency, grain length, amylose content and gelatinization temperature. For data statistical analysis, simple analysis of variance was firstly performed for grain yield, and then Bartlett's test was done to check the uniformity of the experimental errors. Combined analysis of variance and comparison of means by Duncan's method was performed with SAS software. To evaluate the stability of the studied lines, Lin and Binns and GGE-biplot methods were used. Research findings The results of combined analysis of variance showed that the effects of genotype and year as well as the interaction of year×place and year×place×genotype on grain yield were significant. Therefore, grain yied stability of the studied genotypes was evaluated using Lin and Binns and GGE-biplot methods. The results of Lin and Binns method indicated that two genotypes Gilaneh and 19603 (Hashemi/IR74720-85-1-2-1), with the lowest intra-location variance, were the most stable genotypes in this experiment. The results of GGE-biplot graphical method also showed that the genotypes 19607, Hashemi and Gilaneh, which formed the vertices of the polygon in the grain yield biplot, were the best or the weakest genotypes in some environments or in all environments. Also, the simultaneous evaluation of stability and grain yield of the studied genotypes identified the promising line 19603 as the best genotype. The graph of ideal genotype also showed that the promising line 19603 had the smallest distance from the hypothetical ideal genotype compared to other genotypes, so it was the best genotype of this experiment. Conclusion The results of stability analysis of rice genotypes using Lin and Binns and GGE-biplot methods introduced genotype 19603 as the most stable genotype of this experiment. This promising line along with the promising line 19607 produced the highest average paddy yield in all studied environments. These genotypes with the number of days to 50% flowering less than 95 days, grain length more than seven mm, and medium amylose content and gelatinization temperature, were considered as genotypes with mid-maturing, long-grain (Sadri) and good cooking quality. Therefore, two promising lines 19603 and 19607 are suggested for cultivar introduction programs. [ABSTRACT FROM AUTHOR]