Wheat is one of the main sources of calorie and protein in developing world and it is grown in diverse agroecological environments from dry/humid to very cold areas. The wheat grown in cold areas requires vernalization to go to generative stage and the vernalization (Vrn) genes are associated with cold tolerance. International Winter Wheat Improvement Program (IWWIP) is a joint program between Government of Turkey, International Maize and Wheat Improvement Center (CIMMYT) and International Center for Agricultural Research in Dry Areas (ICARDA). The main objective of the program is to develop winter/facultative wheat germplasm for the Central and West Asia region and germplasm exchange globally. IWWIP utilizes the diverse agro-climatic conditions of Turkey for breeding winter/facultative wheat varieties suitable for the region. The advanced breeding lines are annually distributed to more than 80 cooperators in more than 40 countries. The germplasm developed by IWWIP has been utilized both as parents and directly as varieties. More than 90 varieties originating from IWWIP were released in 12 different countries. Two hundred and one genotype coming from diverse origins with different winter adaptation were tested for cold tolerance at -15, -17 and -190 C with 3 replications under controlled conditions in growth chambers. Survival rates of the genotypes were determined for each temperature. The material was genotyped including Vrn genes. ANOVA analysis was done to determine the effect of Vrn genes, combination of Vrn genes and origins of the material on cold tolerance. The material was divided into 5 groups based on their geographical origin. Based on the Vrn genes combinations, there were 7 groups (6 main groups and one others with 11 different gene combinations with small number of genotypes within each group). While 11 spring alleles were present in Vrn-A1 locus, winter alleles were found in 188 genotypes. The respective number of genotypes for the Vrn-B1 and VrnD1 were 55; 146 and 24; 177 for spring and winter alleles. The comparisons were made among the groups and among the Vrn gene combinations. There were statistical differences for cold survival when temperatures -15, -17, -19oC were applied: 84.6 %, 67.3 % and 41.2 %, respectively. There were no differences among the groups of genotypes at -15oC. The differences were clearly seen at -17oC and -19oC. The highest survival rate was in USA germplasm at -19oC with 49.4 %. The highest survival rate at -19oC was obtained from the genes combination: Vrn-A1 spring; Claire-type; Jagger-type; vrnB1_winter; Vrn-D1.