This study was undertaken to find out national level changes in area, production and yield of two major staple crops wheat and potato in Bangladesh. The time series of secondary data was collected from yearbook of agricultural statistics under Bangladesh Bureau of Statistics (BBS) and used for the statistical analysis during the thirty-year period of 1989/90-2018/19. Moreover, selected data were divided into two groups and regarded as segment (1989/90-2003/04, 2005/06-2018/19) to examine the significant level in each crop. The results of different statistical techniques showed that wheat cultivated area and production were satisfactory level but yield was not too much standard in context of country demand. In the case of potato, yield as well as cultivated area and production were crossed the significant level and fulfilled the demand of population. In recent few years, the ratio of potato production rapidly increased, compared with the cultivation area. Based on segment (period) analysis, at the first half wheat production was always below, compared with the area but second half nine years saw slightly improved. On the other hand, in both segment potato growth rate in area, production and yield were increased throughout the study period. The highest instability was also shown in area, production and yield of potato during whole as well as segmented period. There was always a positive relationship between country’s demand and supply. Both wheat and potato are considered as staple crops and based on the productive capability over cultivated area, potato showed the higher productivity for the country of Bangladesh. In consequences, potato consuming demand also rapidly increased all over the country, compared with past respectively.