According to the Nature of Science Educational Standards incorporated in the New Core National Standards introduced in the Thai Educational Reform System of 1999, science teachers should emphasize three aspects of the nature of science in their instruction: scientific knowledge, scientific inquiry and scientific enterprise. However, the pilot study using an open-ended questionnaire to survey the 37 science teachers’ understanding of the nature of science has found that only half of participants have some conception of the nature of science. Their understanding of the nature of science was generally limited and unclear. The main study aimed to develop and implement the SLS (Sleep-Love-Share) instructional model based on analogy and contemplative education approaches for science teachers to enhance their understanding of the nature of science. The SLS instructional model has three steps of learning as follows: S-Sleep step for participants to relax, L-Love step for participants to combine their knowledge with love, and S-Share step for participants to share their learning and deep listening. The participants were 24 Thai science teachers. The data were collected using a learning journal and a five-point Likert scale questionnaire with open-ended questions for science teachers’ opinions toward the SLS instructional model based on analogy and contemplative education approaches. The data indicated that: (1) The participants (95.83%) could explain the meaning of the nature of science and 83.33% of the participants could explain the three aspects of the nature of science using the analogy process, (2) The science teachers’ opinions toward the SLS instructional model based on analogy and contemplative education approaches after they had studied using the SLS instructional model based on analogy and contemplative education approaches were at high level at 0.05 level of significance. The results indicated that the SLS instructional model based on analogy and contemplative education approaches could be used to enhance the science teachers’ understanding of all aspect of the nature of science.