To measure mobility of dendritic filopodia, complexity of dendritic arborization using method of live imaging in cultured rat hippocampal neurons and to analyze their morphological characters quantitatively. Vectors expressing Green Fluorescent Protein- Fibrous Actin (GFP-F-Actin) and F-GFP were co-transfected into cultured rat hippocampal neurons at 5 d in vitro (DIV 5). Neurons expressing GFP were photographed and analyzed with Metamorph software. Dendritic filopodia was observed to move actively from DIV 7 to DIV 9. The mean density of filopodia was (10.78 +/-3.78)/100 microm, (10.68 +/-2.96)/100 microm and (9.99 +/-3.67)/100 microm (P >0.05), and there were (30.18 +/-14.03)% to (87.36 +/-20.88)% filopodia were mobile (P <0.001). During DIV 7-DIV 14, the total length of dendritic branches grew from (410.74 +/-185.98) microm to (1238.21 +/-418.32)microm (P <0.001) and the number of dendritic branches increased from 18.93 +/-7.23 to 33.60 +/-10.46 (P<0.001). The density of spine was (37.17 +/-6.46)/100 microm at DIV 14. The combination of live imaging with quantitative analysis is a useful method to study dendritic morphological development in vitro, including indicators of dendritic filopodia, dendritic arborization and spines.