Chimeric antigen receptor-T (CAR-T) cell therapy is a precise immunotherapy for lymphoma. However, its long-term efficacy faces many challenges related to tumor cell heterogeneity, interference from immunosuppressive microenvironments, CAR-T cell exhaustion, and unmanageable adverse events. Diverse modifications have been introduced into conventional CAR-T cells to overcome these obstacles; examples include addition of recognition sites to prevent immune escape, coupling of cytokine domains to enhance killing ability, blocking of immune checkpoint signals to resist tumor microenvironments, and inclusion of suicide systems or safety switches to improve safety and flexibility. With increasing understanding of the importance of metabolism and epigenetics in cancer and cytotherapy, glycolysis, methylation, and acetylation have become crucial CAR-T cell therapeutic targets. Universal and in situ CAR-T cells are also expected to be used in clinical applications, thus providing hope to patients with relapsed/refractory lymphomas.