Provided is a composition that contains an antisense oligonucleotide to a micro RNA and is capable of inhibiting the growth of cancer cells. The present invention, as one aspect, relates to a composition for suppressing the growth of human cancer cells, the composition containing an antisense oligonucleotide to a micro RNA, wherein the micro RNAis selected from the group consisting of hsa-miR-133a, hsa-miR-133b, hsa-miR-346 and hsa-miR-361-3p. The present invention, as another aspect, relates to a composition for suppressing the growth of human head/neck cancer cells, the composition containing an antisense oligonucleotide to a micro RNA, wherein the micro RNA is selected from the group consisting of hsa-miR-92a, hsa-miR-133a, hsa-miR-133b, hsa-miR-139-5p, hsa-miR-197, hsa-miR-328, hsa-miR-346, hsa-miR-361-3p, hsa-miR-605, hsa-miR-766, hsa-miR-1228, hsa-miR-1252, hsa-miR-1260 and hsa-miR-1271.