【目的】 通过完善铃木氏果蝇Drosophila suzukii（Matsumura）未成熟期的形态学研究，为双翅目果蝇科未成熟期的形态学及铃木氏果蝇的生物学、生态学及田间综合防治研究提供理论基础。【方法】在解剖镜下详细观察了卵、幼虫、蛹3个虫态的发育变化过程，使用解剖镜自带测量尺对该虫的卵粒长宽、不同龄期的幼虫体长宽及骨化结构长度、蛹粒长宽进行了测量。【结果】 卵期观察到了3个标志阶段：初产卵、预孵卵、破壳卵；卵粒长0.57~0.61 mm，宽0.18~0.21 mm，且具有两条长于卵粒长度的呼吸丝。幼虫期通过Crosby生长法则验证幼虫的骨化结构长度指数均小于0.1，说明幼虫龄期划分为3龄是合理的；1~3龄的幼虫平均体长宽分别为0.72 mm×0.23 mm、2.17 mm×0.51 mm、4.06 mm×0.94 mm，相邻龄期的体长宽范围较为接近，其中1龄与2龄幼虫的体宽范围有重复；1~3龄的口钩平均长度分别为0.08、0.15、0.24 mm，头咽骨平均长度分别为0.04、0.08、0.16 mm，相邻龄期的口钩、头咽骨长度范围无重复；同时，对比了不同龄期幼虫的形态差异。蛹期观察到了2个标志阶段：预蛹、蛹；蛹粒长为3.1~4.1 mm，宽为0.9~1.3 mm，且具有两个呼吸角。【结论】 本文详述了铃木氏果蝇从卵至蛹羽化为成虫的全过程以及未成熟期各虫态的形态特征，测量了幼虫骨化结构的长度作为龄期划分的精确依据，提出了通过观察体长宽、体色、体形、骨化结构及后气门的形态差异对幼虫龄期进行快速粗划分的方法。

[Objectives]  To provide further information on the morphology of the Drosophilidae and, in particular, improve understanding of the biology, ecology, and IPM, of the immature stages of Drosophila suzukii. [Methods]  The development of eggs, larvae and pupae was observed under an anatomical lens, and a measuring scale on the lens was used to measure the length and width of eggs, and the bodies and skeletons of different larval instars and pupae. [Results]  Three distinct phases: the primiparous, pre-hatching, and hatching phases, were observed during the egg stage. D. suzukii eggs are 0.57-0.61 mm long and 0.18-0.21 mm wide. The two respiratory filaments are longer than the egg. Larval instars could be divided into three stages on the basis of mouth hook and cephalopharyngeal skeleton length. “Crosby Rules” verified that the Crosby ratios of these measurements were less than 0.1, so it was reasonable to divide larvae into three different instars on this basis. The average length and width of the bodies of the different larval instars were 0.72 mm×0.23 mm, 2.17 mm×0.51 mm and 4.06 mm × 0.94 mm, respectively. The ranges of body length and width measurements among the different larval instars was close; those of the 1^st and 2^nd larval instars were overlapping. The average length of the mouth hooks of the different larval instars was 0.08, 0.15 and 0.24 mm, respectively. The average length of cephalopharyngeal skeleton of the different larval instars was 0.04, 0.08 and 0.16 mm, respectively. The ranges of mouth hook and cephalopharyngeal skeleton length measurments differed between larval instars. Two marked phases were observed in pupae: namely the prepupal, and pupal stages. D. suzukii pupae are 3.1-4.1 mm long and 0.9-1.3 mm wide. Pupae have two respiratory horns on the top. [Conclusion]  The entire developmental process of Drosophila suzukii, from egg to eclosion, and the morphological characteristics of different immature life stages, were described in detail. Accurate criteria for classifying larval instars were established, although a rapid and approximate classification can be achieved on the basis of body length and width, color, shape, and skeleton and spiracle structure.