Abstract In this thesis we have investigated the effect of coronal mass ejection (CMEs) driven storms on ionospheric total electron Content (TEC) over Debark using Global positioning system (GPS) deployed at Debark station with geographic latitude 13.55 0 N and longitude37.8984 0 E. By using Rinex processing format, the STEC data has been obtained from GPS and converted to the matlab readable code. We plotted the solar and geomagnetic parameters and inferred relation between these parameters with ionospheric total electron content. The Dst (disturbance time index) occurrence date has been correlated with the maximum average CMEs speed Occurrence date. The effect of these CME and CIR were reflected on the geomagnetic disturbance indices Dst depression and ionospheric VTEC increment/decrement. Among the twelve geomagnetic events observed in the year 2015, 91.67% were enhanced ionospheric VTEC over Debark, Amhara region, Ethiopia and only 8.33% were depleted the ionospheric VTEC. We came to conclude that the occurrence of CMEs and CIRs are mostly a proxy for existence of geomagnetic storm that in turn has a positive /negative effect on ionospheric VTEC.