An attempt is made in this paper to understand the dynamics of the relationship between population pressure and agricultural productivity examining the change in the level of land-man ratio with the change in the level of land yield of the districts in Bangladesh during the period 1961-64 to 1974-77. It is hypothesized that land-man ratio will be inversely related to agricultural yield. The hypothesis is supported by data. However, this relationship becomes weak when districts are classified according to their yield levels. But the growth of labour force seems to be related with the growth of output, indicating a dynamic relationship between yield and population pressure. However, the direction of causation is not necessarily from ‘population pressure’ to higher productivity; rather higher productivity also leads to higher density by attracting migrants from other non-developing areas. This movement of population from poor agricultural districts to districts of better agricultural performance has resulted in higher population density in high growth rate districts and lower density in low and negative growth rate districts.