Successful artificial insemination requires successful sperm collection, evaluation and the addition of preservatives toincrease sperm shelf life. Despite many efforts and addition of protective and antioxidant substances, the quality of frozen-thawed sperm is low and the resulting fertility is not acceptable. For this reason, in present research, the cooling method has been used instead of freezing. The aim of this investigation was to evaluate the effect of apricot gum adding to Tris-base diluents on liquid ram semen storage and ewes pregnancy rate. Twenty-five ejaculates were collected from 5 Ghezel rams by artificial vagina in Khalatpushan research station. Average age of rams was 3 years. Semen samples were collected two times per week. After rapid transferring of samples to the laboratory they were evaluated for traits such as volume, wave motion, viability, morphology, total motility, progressive motility, pH and sperm concentration. Diluted semen was divided into four equal parts. One of parts contained only a diluent based on Tris (control group). Into the three treated parts, apricot Gum were added in concentrations of 100µl, 150µl, 200µl per ml diluted sperm (treated groups) and these cases were compared with the control part. In this investigation, it was observed that adding apricot gum at all concentrations of 100,150 and 200µl did not any significant effect on sperm quality up to the third day after cooling in Tris-based diluents (P>0.05), but after the third day of cooling significantly improved sperm quality parameters such as viability, total motility, progressive motility, morphology and membrane health (P<0.05). The differences among treatments parts with different apricot gum concentrations were not significant (P>0.05). In this study, 12 ewes were divided into 4 groups (n=3 ewes) and every group was artificially inseminated by cervical approach with one of diluted sperm parts. The number of pregnancy in ewes inseminated with 0 (control part), 100, 150 and 200µl apricot gum concentrations parts were, 1, 2, 2 and 3 respectively .In general, the results of this study showed that the addition of Apricot Gum to Tris-based diluents increases the quality in short time storage of ram liquid semen. [ABSTRACT FROM AUTHOR]