[Objectives]  To determine the biological characteristics and population dynamics of Frankliniella occidentalis in Lhasa. [Methods]  Life tables for each sex were compiled, and the population dynamics of F. occidentalis on tomato plants in a solar greenhouse was investigated using yellow sticky-card traps. [Results]  The pre-adult developmental time of F. occidentalis was 12.54 d, and that of the second instar nymph was 5.62 d, accounting for 44.8% of the pre-adult period. The probability of eggs surviving to adulthood was 0.598. The average longevity of females was 15.18 d, whereas that of males was 9.64 d. The intrinsic rate of increase (r) and net reproductive rate (R₀) were 0.153/d and 22.817, respectively. Adult F. occidentalis were trapped all year round in the solar greenhouse. The population growth curve was of the “single peak” type, with the peak corresponding to the peak of adult emergence from mid-June to early August. [Conclusion]  The developmental period of second instar nymphs of F. occidentalis in Lhasa city was obviously longer than that of the first instar, and the optimum control period in greenhouses is in early April.