In this paper, with a general & practical attitude to building industry, in order to increase the stability of buildings, the parameters effective in the relationship between midterm and long & short-term compressive strengths of concrete have been checked. So, the trend of the progress of compressive strength concrete during 7, 28, 90, 180, 365 days for a high- consumed (brand of) cement in Tehran Building industry was investigated by making many laboratory concrete mixes (34 mixes & 408 specimens). In these normal concretes with 350 kg/m3 cement_ all prepared in the same condition_ the only variable parameter was cement. The results showed that the average of the ratio of compressive strength was in the form of 7days/28days=75%, 90days/28days=115%, 180days/28days=121%, 365days/28days=125% and the total ratio was 440%. This total ratio is nearly the same for all mixes (Sum of 4 ratio mentioned). To control the permeability of concrete mixes which is one of the indexes affecting durability of concrete, some experiments of the rate of water absorption (Standard Test Method ISIRI19895) and determination of water absorption (Standard Test Method BS-1881-122) for on 28-day specimen has been carried out. So, in average, the initial rate of water absorption was about 58 ×10-4 mm/s1/2 , the secondary rate of water absorption about 178×10-4 mm/s1/2 and water absorption about 5.4%. The comparison of the results of the two tests didn’t show a clear relationship between long-term compressive strength and the permeability of concrete.