随着素质教育与课程改革的深入，学习困难问题越来越得到教育者的关注。导致学生学习困难的原因包括以下几个方面：智力因素，如缺乏合理正确的认知加工过程；非智力因素，如厌学、焦虑等负面情绪；环境因素，如学习环境、家庭环境等。对于学习困难的解决策略则包括培养学生的认知能力、建立和谐的师生关系、实施分层教学等手段让学困生体验成功等方面。学习困难领域一个重要的研究方向是基于具体学科的学习困难成因及转化策略研究，如对化学学习困难的相关研究。这些研究能够对某一具体学科的教学提供借鉴意义，但还可进一步深入到具体学科的具体知识的学习困难研究中。本研究以高中化学的重要知识点——元素化合物知识为依托，通过已有研究和笔者的实践经历明确学生元素化合物学习的现实表现，并以知识分类理论（即分为陈述性知识、程序性知识、策略性知识）为理论依据，重新构建元素化合物知识体系，并结合学生的学习表现对元素化合物学习困难成因做出假设，构建元素化合物学习困难成因的具体维度，并据此进行问卷设计。通过对高一学生进行问卷调查，并对结果进行分析，得出如下的主要结论：在元素化合物学习中，学业成绩好的学生对三类知识的掌握程度更好；与元素化合物学业成绩相关性最强且贡献最大的是陈述性知识，其次是程序性知识，相关性最弱且贡献最小的是策略性知识。元素化合物学习困难的成因包括以下几个方面：⑴陈述性知识方面：物质性质容易混淆，缺乏物质性质与实验现象、实际应用、物质组成之间对应关系的知识，缺乏对无机反应规律的总结；⑵程序性知识方面：缺乏解决问题的思维步骤；⑶策略性知识方面：缺乏意义生成策略、精加工策略和用氧化还原、物质分类相关理论构建元素化合物知识体系的组织策略。进一步根据不同类型知识的教学策略及高中教学实际，提出一系列有针对性的转化策略。

With the development of Education for all-around development and Course innovation , more and more pursuers begin to focus on learning difficulty. Many factors can cause learning difficulty, for example: the intellectual factors, negative emotions, environmental factors and so on. The ways to solve this problem include: training students’ cognition capability, building harmonious relationship between teathers and students and so on.An important research aspect of learning difficulty area is based on the cause and solution of learning difficulty in some subject , such as researches on learning difficulty in Chemistry. Such researches can make a difference on teaching of a given subject and deepen into leaning difficulty in idiographic knowledge of idiographic subject. This study selects an important knowledge of the high school chemistry, namely element compounds, through researches and the author’s experience to find the students' learning performance during element compound’ learning, and then constructs the Elemental compound knowledge structure based on the Knowledge Classification Theory which tell us Knowledge includes declarative knowledge, procedural knowledge and strategic knowledge. In succession, we put forward the hypothesis and the frame of the questionnaire about the causes of element chemical compound learning difficulties.We also did a questionnaire survey of the first grade of senior high school and analyze the result. Through the questionnaire survey, we drew a few important conclusions. in the learning process of element compounds, good-grade students master the three different types of knowledge better. The declarative knowledge is most relevant to element compounds result, and then the procedural knowledge, the least relational knowledge is procedural knowledge. The causes which result in element compounds learning difficulties includes confusing material properties, lacking the knowledge of the relation between material properties and practical application, lacking problem-solving steps, lacking Effective strategies and so on. At last, we give some suggestions to improve the learning difficulties.