The article reviews the importance of pre-mRNA splicing and its study tools in plants. Alternative splicing (AS) enriches transcriptome and proteome diversity, playing a crucial role in plant development and stress responses. The review compares splicing mechanisms in prokaryotes and eukaryotes, highlighting the complexity of eukaryotic splicing. It discusses recent progress in AS studies across different developmental stages and abiotic stress conditions in various plant species. Modern techniques for studying AS transcripts and their protein products are also covered. The article emphasizes the integration of genetic studies, quantitative methods, and high-throughput omics techniques to discover novel transcript isoforms and functional splicing factors, enhancing our understanding of splicing modes in plants. Key findings include the significant impact of AS on plant development, stress responses, and evolutionary processes, with specific examples from *Arabidopsis thaliana* and other plant species.The article reviews the importance of pre-mRNA splicing and its study tools in plants. Alternative splicing (AS) enriches transcriptome and proteome diversity, playing a crucial role in plant development and stress responses. The review compares splicing mechanisms in prokaryotes and eukaryotes, highlighting the complexity of eukaryotic splicing. It discusses recent progress in AS studies across different developmental stages and abiotic stress conditions in various plant species. Modern techniques for studying AS transcripts and their protein products are also covered. The article emphasizes the integration of genetic studies, quantitative methods, and high-throughput omics techniques to discover novel transcript isoforms and functional splicing factors, enhancing our understanding of splicing modes in plants. Key findings include the significant impact of AS on plant development, stress responses, and evolutionary processes, with specific examples from *Arabidopsis thaliana* and other plant species.