Statement of Problem: The problem of dislodged cast restorations is familiar. With the recementation, the need for remake can be eliminated or postponed, as clinical studies have shown that lack of retention is one of the major causes of fixed dental prosthesis failure. Aim of the Study: The purpose of the present study was to determine the relationship between the preparation height and convergency and the retention of complete metal crowns constructed of non precious alloys upon cementation and recementation. Materials and Methods : A total of forty artificial crowns were cast for standardized complete metal crown tooth preparations accomplished with the use of a lathe cut machine on extracted human teeth. The teeth were divided into 2 main groups, each one was 20 samples. Group I (N=20) : Teeth were prepared with 120 taper and 5mm occluso-cervical height. Group II (N=20) : Teeth were prepared with 250 taper and 3mm occluso-cervical height. Each group was further subdivided into two equal subgroups according to type of cement used (N=10 each): Subgroup A: were cemented with Zinc phosphate cement. Subgroup B: were cemented with adhesive resin cement. Retention was evaluated by measuring the tensile force required to dislodge the crowns from the tooth preparations in a universal testing machine. Subsequently, the tooth preparations were scraped clean and polished with prophylaxis paste, and the intaglio surfaces of the artificial crowns were ultrasonically cleaned and airborne-particle abraded with 50-μm aluminum oxide powder prior to recementation. The data were analyzed with 3-way repeated-measures ANOVA and Tukey’s HSD test (α=.05). Results: Analysis of measurements disclosed a significant difference for the preparation taper and height (P<.001). Also, there was a statistically significant difference between the retention of the first cementation and the second cementation (P<.001). Group I showed statistically higher mean retentive strength 4.6 ± 1.2 MPa than Group II 3.1 ± 0.8 MPa. Conclusion: Tooth preparation height and taper had a direct effect on the initial cementation and recementation strength of complete metal crowns.