Discovery of the first planetary system by direct imaging around HR 8799 has made the age determination of the host star a very important task .
This determination is the key to derive accurate masses of the planets and to study the dynamical stability of the system .
The age of this star has been estimated using different procedures .
In this work we show that some of these procedures have problems and large uncertainties , and the real age of this star is still unknown , needing more observational constraints .
Therefore , we have developed a comprehensive modeling of HR 8799 , and taking advantage of its \gamma Doradus-type pulsations , we have estimated the age of the star using asteroseismology .
The accuracy in the age determination depends on the rotation velocity of the star , and therefore an accurate value of the inclination angle is required to solve the problem .
Nevertheless , we find that the age estimate for this star previously published in the literature ( [ 30,160 ] Myr ) is unlikely , and a more accurate value might be closer to the Gyr .
This determination has deep implications on the value of the mass of the objects orbiting HR 8799 .
An age around \approx 1 Gyr implies that these objects are brown dwarfs .