The quality of the surface layer of concrete must be improved to ensure the durability of concrete structures. When the surface quality of concrete deteriorates, the deterioration factors CO2 and Cl− penetrate the concrete from concrete surface, causing reinforcement corrosion, etc., resulting in the possibility of concrete cracks. Therefore, the surface quality of the concrete may be investigated at the construction site at an early age after it has been constructed, and additional measures implemented if deemed necessary. Currently, simple air permeability and water absorption tests are sometimes used, but the problem is that they are time-consuming and arduous. In this study, we attempted to estimate surface quality using handheld ultrasonic measurements. Concrete specimens were also prepared using different water-cement ratios and cement types to achieve different surface quality. The tests were also conducted after varying the number of curing days and the number of days exposed to the air after curing of those concrete specimens. The relationship between curing days and ultrasonic speed was clarified. The ultrasonic speed at the same number of curing days were clarified as well. As an evaluation index, a simple water absorption test using a non-destructive test method was also carried out and the results of both measurements were compared. If the ultrasonic velocity is measured within a short period of time after the curing has been completed, it will be affected by increased propagation and increased strength due to unevaporated water in the specimen. As a result, these effects prevented the measurement of stable values and did not correlate well with the water absorption rate. However, the period of exposed to the air was extended after curing was completed, stable values could be measured and high correlation with water absorption rate was observed.