Salinity is one of the environmental factors that have a critical influence on the emergence and plant growth and establishment. The determination of salinity tolerance threshold is a useful criterion to choose soil and irrigation water for cultivation of halophytes. In order to determine salinity tolerance threshold in Kochia, an experiment was performed in greenhouse in a complete randomized block design with five replications in two stages. In the first stage, the experiment was performed with salinity levels of 0, 10, 20, 30 and 40 dS m^-1 NaCl. In this stage, seeds were able to emerge up to the salinity of 20 dS m^-1 and the emergence percentage in salinity levels of 0, 10 and 20 dS m-¹, was 85, 55 and 28%, respectively. In order to determine the full-scale of salinity tolerance threshold in Kochia, the second experiment was conducted. At this second stage, treatments were different levels of salinity equal to 20, 22, 24, 26 and 28 dS m-1 NaCl. Kochia seedlings were able to emerge up to the salinity of 26 dS m^-1 NaCl. In general, with increasing the levels of salinity seedling emergence percentage, the length of seedling, fresh and dry weight of shoot and dry matter percentage was decreased. According to the results, salinity tolerance threshold for seedling emergence and performance of Kochia under controlled conditions was 26 dS m^-1.