Based on experimental phonetic studies and phonological analyses, a framework of standard Chinese syllable structure is developed. This paper argues that the nasal or off-glide of a diphthong is coda, instead of nuclear, and that the glide is a feature of onset, instead of the first part of rhyme. It means that the full syllable in standard Chinese has two parts, onset and rhyme. There are three kinds of onset, namely, C (consonant), G (glide), and CG, and there are two kinds of rhyme, V (vowel) and VK (nasal or off-glide). No matter whether a syllable is a V or a VK, it has two morn. Full syllables in standard Chinese are all long syllables.