To learn the role of miR-202 in the zebrafish embryonic development, miR-202 expression was detected using qRT-PCR and WISH. The results indicated that miR-202 is a maternal molecule and expressed continuously during the zebrafish embryonic development, especially at the early stages. Knockdown of miR-202 was performed by microinjecting the locked nucleic acid modified antisense oligo of miR-202. The results showed that antisense oligo of miR-202 decreased miR-202 level significantly, accompanied with an early termination of the zebrafish embryonic development at around 4 hpf. And miR-202 inhibition induced early termination could be partly rescued by co-injection of pre-miR-202, indicating that miR-202 is required for the early zebrafish embryonic development. The present study for the first time unveils the essential role of miR-202 for the zebrafish embryonic development.