本論文利用Hinotori衛星所裝載的電子溫度計,量測自1981年3月至1982年6月間電離層於六百公里高之電子溫度,研究在地震發生前後期間電離層電子溫度之變化,並將量測資料與經驗模式做比對,討論電子溫度於地震期間之變化。在此量測期間,選取了位於台灣和菲律賓附近共11個規模大於6之地震,在其中4個地震中發現在地震前約5日開始,量測電子溫度與經驗模式出現了很大的差異,量測值明顯的低於經驗模式,此現象一值持續至地震約後5日,且出現差距最明顯之時間主要在午後增溫的時段(1500LT ~ 2000LT),推測此溫度下降的原因是電離層在地震期間受到地震擾動,造成電離層中的電荷分布改變,因而產生西向電場所造成,除了電子溫度變化外亦利用DE2衛星量測地震期間震央附近之輻射電場,研究地震期間之電離層電磁現象。 Pre-seismo-ionospheric signatures are studied by comparing variations in the electron temperature during the occurrence of large earthquake (M≧6.0). The ionospheric electron temperature was measured by electron temperature probe (ETP) on board Hinotori satellite during the period form March 1981 to June 1982. Eleven earthquakes in the vicinity of Taiwan and Philippines area are isolated and examined. Four of them show that anomalous deviations between observed Te and the associated empirical model around the dusk period or afternoon overshoot period(1500LT – 2000LT) appear from about 5 days before to 5 days after the earthquakes. A westward electric field possibly generated during the earthquake preparation period due to the change of the charge distribution. We also discuss the ELF(Extremely Low Frequency) emission observed by DE2 satellite.