Various carbon nanotubes (CNTs) including aligned arrays, Y-branching and some other novel morphologies have been catalytically grown on anodic porous alumina template (APAT) and on the alumina-supported catalysts with methane (or benzene) as carbon source under microwave plasma assistance below 520degreesC. The growth process could be simply operated since neither heating nor bias-voltage was applied to the catalysts or APAT. The results presented in this paper riot only greatly richened the nanostructures of carbon family but also provided with a new technique path for synthesizing CNTs or some other nanostructures with the characteristics of low-temperature which has some special advantages or applications.