Competitive endogenous messenger RNAs (ceRNAs) affect other RNAs transcription through competitively binding common microRNAs (miRNAs). In this study we identified long non-coding RNA (lncRNA) MALAT1 can function as a ceRNA of cell division cycle 42 (cdc42) 3′UTR in inducing migration and invasion of breast cancer cells via miR-1. We found that miR-1 bound both MALAT1 and cdc42 3′UTR directly. Further study showed that MALAT1 induced migration and invasion of breast cancer cells while reduced the level of cdc42. Our results suggest that MALAT1 regulated migration and invasion of breast cancer cells via affecting cdc42 through binding miR-1 competitively. •Verifying MALAT1 does promote migration and invasion of breast cancer cells.•MiR-1 plays an important role in MALAT1 and cdc42 regulating network.•MALAT1 competitively binds miR-1 with cdc42 to promote migration and invasion of breast cancer cells.