This study explores the glottalization of Taiwan Min checked tones 3 and 5 with a CV [p t k] syllable structure. Electroglottography (EGG) supplements acoustic data on disyllabic words with checked tones collected from 40 speakers from five dialect regions. The results indicated that a final coda can be realized as a full oral/glottal stop closure, an energy dip at vowel's end, an aperiodic voicing at vowel's end, or a coda deletion. Over 80% of codas and less than 20% of /p t k/ codas were deleted. The undeleted /p t k/ codas were more likely to be produced with a full stop closure among tone 3 and sandhi tones. Glottal contact quotient (CQ-H) distinguished tones 3 and 5 from unchecked tones 31 and 51, respectively. In sandhi positions, the vowels of tone  /3/ were produced with a longer CQ-H, lower H1∗-A3∗ and a higher Cepstral Peak Prominence (CPP), suggesting a longer close phase, a more abrupt glottal closure and more periodic voicing than tone  /5/. In juncture position, coda deletion and the merging of H1∗-A1∗, H1∗-A3∗ and A1∗-A2∗ of tones  /3/ and  /5/ suggest a sound change among checked tones.