Abstract: Euglena have important scientific value for studying biological evolution and chloroplast endosymbiosis and provide high value-added dietary supplements as well as high-quality feedstock for biofuel production. Studies of Euglena have been mainly explored by physiological and biochemical methods. With almost completed Euglena genome, we employed diverse OMIC techniques such as single cell RNA-seq, transcriptomic, proteomic, methylomic, and metabolomics to study the chloroplast development and the communication between chloroplast and nucleus. We hooked up some interesting genes and microRNA targets. Little progress has been achieved in genetic engineering of Euglena due to lack of efficient techniques for genetic operation. In here, we reviewed the methods in genetic transformation of Euglena, such as antibiotic biomarkers, biolistic, electroporation, glass beads and Agrobacterium transformation techniques, RNAi, potential CRISPR/cas9, and cpf1 genome editing, to provide a reference for functional genomics and biotechnology of Euglena.