Objectives: The aim of this study is to evaluate the effect of margin configuration (Rounded shoulder and Deep chamfer) and pattern construction technique (Machinable and Conventional wax pattern) on marginal adaptation of pressable all-ceramic crowns. Statement of the problem: All -ceramic restorations are nowadays widely accepted in the anterior and posterior regions. However, their marginal accuracy is of paramount clinical significance. Although finish line design, could contribute to precision of an all-ceramic restoration, it is unclear which type is the best. Additionally , the pattern construction technique is a sensitive process that affects the marginal fit of restorations. Materials and methods: Twenty extracted intact human mandibular second molars collected, cleaned and stored in saline until use. All teeth mounted in epoxy resin blocks using a specially constructed mould and paralleling device. According to the finish line configuration the mounted teeth prepared by a specially fabricated copy milling machine then divided into two main groups: Group I:(n=10) Rounded Shoulder finish line. Group II: (n=10) Deep chamfer finish line. According to the pattern construction technique for the pressable all-ceramic crowns, each group was further subdivided into two subgroups: Subgroup A: Conventional wax pattern technique. Subgroup B: Machinable pattern technique. All patterns invested and pressed into IPS e.max press all-ceramic crowns according to the manufacturer instructions. All-ceramic crowns of both groups placed onto their corresponding teeth and the vertical marginal gap distance between the all-ceramic crown margin and the finish line of the tooth at each surface measured using a stereomicroscope. Two-way (ANOVA) was used to detect the effect of finish line design, pattern construction technique and their interactions. Student’s t-test was used for detailed comparisons between the two finish lines and the two techniques. Results: There was no statistically significant difference between mean vertical marginal gap distance of the deep chamfer finish line (0.044 ± 0.013 mm) and the rounded shoulder finish lines (0.036 ± 0.009mm). There was no statistically significant difference between mean vertical marginal gap distance of the conventional pattern construction techniques (0.037 ± 0.014 mm) and the machinable pattern construction technique (0.044 ± 0.008 mm). The rounded Shoulder conventional pattern technique showed statistically significant lowest mean vertical marginal gap distance values 0.031mm. Conclusions: The finish line configuration (Rounded shoulder and deep chamfer) did not affect the marginal adaptation of IPS e-max Press all-ceramic crowns constructed by different pattern techniques.