The aim of the present study was to examine Cdc42 expression in cervical cancer and explore its effects on invasion and migration capability of cervical cancer cells. Immunohistochemistry was used to detect Cdc42 expression in normal cervical tissues as well as CIN I or below, CIN II or above, and cervical cancer tissues. Western blot analysis was used to explore Cdc42 expression in normal cervical cell line Crl-2614 and cervical cancer cell line HeLa. Plasmids of constitutively active Cdc42 (Cdc42 CA), wild-type Cdc42 (Cdc42 WT) and dominant negative Cdc42 (Cdc42 DN) were transfected, respectively, into HeLa cells to investigate the impacts of Cdc42 on migration and invasion of cervical cancer cells using Transwell and on cytoskeleton microfilaments using confocal microscopy after immunofluorescence staining. Cdc42 expression was gradually increased in the order of cervical tissues with CIN I or below, CIN II or above and cancer, showing significant difference (P<0.05), and was significantly higher in HeLa cells than in Crl-2614 cells (P<0.05). Migration ability of HeLa cells transfected with Cdc42 CA was significantly higher than that of non-transfected, as well as Cdc42 WT- or Cdc42 DN-transfected HeLa cells (P<0.05). Overexpression of Cdc42 CA can promote filopodia formation in HeLa cells. We concluded that Cdc42 overexpression significantly improved the ability of cervical cancer cells to migrate possibly due to improved pseudopodia formation.