The Terrestrial Laser Scanning (TLS) has the characteristics of non-destructive measurement, and its point cloud information acquired from TLS allows obtaining accurate forest attributes through visualization and automated extraction. The purposes of this study include using TLS to obtain point cloud information and discuss different methods to extract Diameter at breast height (DBH) and height (H) within small plot, and we also discuss the impact of point cloud generation in different resolution and station number settings. The results showed that the DBH and H measured by TLS were not significantly different from the measured values in the manual extraction and semi-automatic extraction detection methods. In addition, when the scanning resolution is 1/4(43.70 MPts) and 1/2(174.80 MPts), there is no significant difference between the measured DBH, H and the measured value, and the accuracy does not increase when the resolution is 1/2(174.80 MPts). Therefore, we can obtain the accurate DBH at the scanning resolution of 1/4(43.70 MPts); and the number of scanning stations is positively correlated with the DBH and H extraction accuracy. Therefore, the number of stations should be more than four stations.