The objectives of this study are to identify and explain the different between population dynamic and agricultural productivity in LDC's and MDC's; as well as to investigate the relationships between population dynamic and agricultural productivity in LDC's and MDC's. The sample was involved 109 countries. According to the Human Development Report (2019), 58 of these countries are considering as LDC's, while others 51 are considering as MDC's. Means, standard deviation, T test, and Spearman correlation coefficients used as statistical techniques. Results of T test indicate a different statistically significant between LDC's and MDC's for the all dependent and independent variables, except the total population variable. The results of Spearman's correlation coefficients showed that the highest index of crop production is likely to occur among LDC's that have a high population growth rate and more dependency ratio, while it occurs among MDC's with the highest percentage of the population age composition (0-14). Furthermore, the results suggest that the highest food production index are more likely to occur among MDC's that have the more growth rate of population, more growth rates of urban population, highest rate of net migration, lowest dependency ratio, highest percent of population age composition (0-14 and 15-64), and lowest percent of population age composition (65+), while it occurs among LDC's with the high population growth rate. Moreover, the results suggest that the highest livestock production index are more likely to occur among MDC's that have the highest growth rate of population, highest growth rate of urban population, highest rate of net migration, less dependency ratio, highest percent of population age composition (15-64), and lowest percent of population age composition (65+).