One hundred and nine patients with squamous cell carcinoma of lung, including 67 cases had bronchoscopic biopsy sampling and 42 cases had surgical samplings, were studied and histologically classified according to WHO Classification - 1999. Results indicated that: (1) Male/ Female ratio were 4.17/1 to 6.44/1; (2) Four variants of squamous cell carcinoma were found; (3) Identification of exact those variants required larger samplings or surgical sampling from different sites of tumors; (4) Histological criteria for every variants were presented and discussed.