Proponents of navigated hip arthroplasty have suggested that it may increase the precision of acetabular component placement. We conducted a systematic review and meta-analysis to evaluate the validity of this theory. We searched, in duplicate, MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials for randomised trials comparing the use of computer navigation with the freehand technique for acetabular cup placement within the desired alignment. We assessed the methodological quality of the studies and abstracted the relevant data. Tests of heterogeneity and publication bias were performed. From the three studies included, there was no evidence of heterogeneity between studies. A total of 250 patients were entered into the analysis. The beneficial odds ratio for the number of outliers was 0.285 (95% confidence interval [CI]: 0.143 to 0.569; p < 0.001). We conclude that navigation in hip arthroplasty improves the precision of acetabular cup placement by decreasing the number of outliers from the desired alignment.