Tujuan penelitian ini untuk menyelidiki efek harga diri siswa terhadap kemampuan berbicara pada siswa dan mencari tingkat harga diri yang lebih berpengaruh terhadap kemampuan bicara siswa. Tiga puluh siswa terpilih sebagai sampel. Data diperoleh dengan menyebarkan kuisioner mengenai harga diri siswa dan tes berbicara. Data dianalisa menggunakan one-way Anova. Hasil analisa menunjukkan nilai-f lebih besar daripada table-f (81.75 >33.50) dengan p<0.001. H0 ditolak dan H1 diterima. Harga diri siswa mempunyai efek terhadap kemampuan berbicara mereka. Hasil tes juga menunjukkan siswa dengan harga diri tinggi meraih skor tertinggi dalam kemampuan berbicara dengan nilai rata-rata 87.40, harga diri normal meraih nilai rata-rata 77.80, harga diri rendah meraih nilai rata-rata 66.80. Harga diri tinggi mempunyai efek lebih baik terhadap kemampuan berbicara siswa.The research objectives are to investigate the effect of students’ self-esteem on their speaking ability and to find out which is better among low, normal and high self-esteem on their speaking ability. Thirty students were selected as samples. The data were gained by administering questionnaire about the students’ self-esteem, and speaking test. The data was analyzed by using one-way Anova. The result of the analysis shows f-value is higher than f-table(81.75 >33.50) with p<0.001. H0 is rejected and H1 is accepted. It means that students’ self-esteem has effect on their speaking ability. The result also shows that students with high self-esteem reaches the highest score in speaking ability with mean of 87.40, normal self-esteem reaches mean of 77.80, and low self-esteem reaches mean of 66.80. High self-esteem has better effect on students’ speaking ability.Keywords: attitude, inhibition, risk-taking, self-esteem.