<p>Teacher can use classroom dialogue to facilitate students’ understanding of nature of science (NOS). However, there is not any dialogic scheme that characterises meaningful dialogue of NOS, as well as analytic techniques that characterise sequential connections between dialogic moves. A dialogic scheme comprising eight dialogic codes across three levels was developed. An innovative learning analytic approach, ordered network analysis (ONA), was used to characterise the <i>sequential connections</i> between dialogic moves. ONA creates a network of ordered connections between codes, allowing visual and statistical comparisons in terms of sequential appearance of codes. As such, this study compares the sequential dialogue between an experienced teacher and an inexperienced teacher who follow the same teaching and learning sequence of NOS in Hong Kong. This exploratory finding showed that the experienced teacher scaffolded classroom dialogue from setting foundation to contextualised understanding of NOS, while the inexperienced teacher did not exhibit such an observation. The use of ONA, coupled with the new scheme of dialogue of NOS, can inform professional development of prospective and inexperienced teachers. </p>