Objective To investigate the roles of miR-145 in lung adenocarcinoma (LAC) and to clarify the regulation of N-cadherin by miR-145. Results In 57 paired clinical LAC tissues, diminished miR-145 was significantly correlated with the lymph node metastasis and was negatively correlated with N-cadherin mRNA level expression. Wound healing and transwell assays revealed a reduced capability of tumor metastasis induced by miR-145 in LAC. miR-145 negatively regulated the invasion of cell lines through targeting N-cadherin by directly binding to its 3'-untranslated region.Silencing of N-cadherin inhibited invasion and migration of LAC cell lines similar to miR-145 overexpression. Conclusions MiR-145 could inhibit invasion and migration of lung adenocarcinoma cell lines by directly targeting N-cadherin.