English language teaching in Indonesia continues to improve the communicative ability of students. To support English language mastery, school subjects such as mathematics, science, and technology are taught in English. However, the main problem faced by prospective science teachers is their limited English proficiency which leads to limited English communication. Therefore, a tool called "Science Instruction in English Audiobook" was seen as one of the media which can help prospective science teachers to practice the teaching skills in English. Hence, this study aims to develop and evaluate a "Science Instruction in English Audiobook" to help prospective science teachers improve their science teaching skills in English. The skills of science teaching in English were then observed to find out the effectiveness of the audiobook. The subjects were 65 prospective science teachers. The research design was Research and Development consisting of problem analysis, literature study, product design, product validation, revision, trial, revision, application, and revision. The "Science Instruction in English Audiobook" product has been successfully developed. The product is a sound recording in .mp3 format with a duration of almost 1 hour 3 minutes 43 seconds. The audiobook contains science vocabulary material (physics, chemistry, and biology) and teaching skills in English. Following the research design steps, the product has been validated by material, media, and language experts. Based on the validation from the experts, it can be stated that the audiobook product is valid with an accumulated percentage of 98% which means it is feasible to be used as a learning resource to develop the English skills of prospective science teachers. Moreover, it has been found that audiobooks can help prospective science teachers to practice effective science teaching skills in English.