Abstract: Based on previous research, in this paper we first summarize knowledge of morphological types, morphological features (including prominent and degenerate ones), and geometrical parameters of lunar impact craters.To help comprehensive understanding of morphological features of most lunar craters in the context of the lunar structure and evolution, we further examine morphological-feature diversities among different types of lunar craters in different areas.This is mainly through our detailed analysis of statistical relations between depth-to-diameter ratios and diameters for lunar craters using the database LU60645GT.The database LU60645GT was complied by Goran Salamunic'car et al.(2012) from the high-resolution data obtained by the LOLA instrument of the LRO mission.We present the results of these relations and the statistical relations between depths and diameters.Our results reveal significant differences between depth-to-diameter ratios of impact craters of three diameter ranges, i.e., diameters below 15km, diameters from 15km to 140km, and diameters above 140km.Our results also show significant differences between depth-to-diameter ratios of craters in three lunar areas, which are for maria, highlands, and the South-Atiken basin, respectively.The paper finally provides results about morphological features of young craters in the three lunar areas.Our main conclusions are as follows.(1) For young craters depth-to-diameter ratios statistically increase with small diameters but statistically decrease with large diameters.(2) For young craters depths statistically increase with diameters, but the increases are milder for diameters above 18km compared to those for diameters below 18km;the increases become obviously milder for diameters above 30km, (3) For young craters with diameters below 15km their depths and diameters are in a tight linear correlation.(4) For young craters with diameters above 15km their depth-to-diameter ratios and diameters are in tight power-law correlations.(5) Average depth-to-diameter ratios of craters in highlands are larger compared to average depth-to-diameter ratios of craters in maria and the South-Atiken basin.