Topic “Ellipse” is in Geometry 10 curriculum for Vietnamese high schools; mathematics contents of the topic are difficult for learners to remember. In order to increase the quality of teaching this topic, we used the GeoGebra as a teaching tool. In this paper, we report the how to  apply the GeoGebra dynamic software to teaching contents related to Ellipse to 10^th grade students and the results of this application. The remarkable findings obtained were:

(1) Students’ learning outcomes were relatively high;

(2) Students’ attitude towards teaching “Ellipse” with GeoGebra was positive.