Introduction. In this paper, we present the results of comparing the mathematics pedagogy knowledge about number and operations that Spanish future primary teachers showed in TEDS-M (Teacher Education and Development Study in Mathematics), first, with the future primary teachers? knowledge of OECD countries that also participated in the study - Norway, Germany, Chile y Poland -; and, secondly, with the future primary teachers´ knowledge of the participating countries which had followed program-types with similar purposes and characteristics to the Spanish program - China-Taipei, Singapore, United States, Philippines and Switzerland -. Method. Data analysis will be based on categories that characterize the pedagogical knowledge required to answer correctly the questions in this conceptual domain. We established criteria for assessing the responses of student teachers for calculating the corresponding parameters. Results. We found that Spanish prospective teachers have lower results, in general, than the other OECD countries and the countries of its group with similar training programs. The Spanish scores are lower than Norwegian, Swiss and Singaporeans scores in all aspects considered. Spain obtained higher scores than Philippines and Chile and next to the U.S.A. Discussion: Comparing the results of the OECD countries that have participated in two international studies, TEDS-M and TIMSS 2011 - Spain, Poland, USA, Norway, Germany and Chile -, we find that the relative position of the country ranking is the same for number and operations. Spanish results in TIMSS are just above Poland and Chile and below the rest. The results obtained in this study may be useful in the current syllabi design process for the El ementary Teacher grade.