This paper deals with the comparative study of foF2 diurnal variation between the Dakar and Ouagadougou stations during shock activity of variable duration (one-day, two-day and three-day shock) for the solar minimum and maximum phases of cycle 21-22. At solar minimum, the curves of the diurnal variation of foF2 of two stations exhibit the signature of vertical drift indicating the presence of a strong electrojet. Except for the one-day shock, the ionization is strong at the Dakar station compared to the Ouagadougou station during this phase throughout the day. On the other hand, during the solar maximum, globally, the graph of Dakar shows the afternoon profile while that of Ouagadougou produced the profile of the morning peak tending towards that of the plateau profile. During this phase, we record a high ionization at the Dakar station compared to the Ouagadougou station from midday until sunrise.
