MicroRNAs (miRNAs) are naturally occurring, small non-coding RNAs that mediate posttranscriptional regulation. Based on the level of sequence complementarity, miRNAs lead to the degradation of target mRNAs or the suppression of mRNA translation, thereby inhibiting the synthesis of proteins and achieving the regulation of genes. miRNAs, which exhibit tissue- and temporal- specific expression, are important negative regulatory RNAs that decrease the levels of other functional genes. miRNAs play a crucial role in disease progression and prognosis and thus exhibit potential for developing novel therapeutics. Due to the instability of miRNAs and their complex environment, including degradation by nucleases in vivo, the safety and effectiveness of miRNA delivery has become the focus of recent attention. Therefore, we discuss some representative advances related to the application of viral- and nonviral-mediated miRNA delivery systems and provide a new perspective on the future of miRNA-based therapeutic strategies.