© 2015 Elsevier Ltd. Wave resonance in the narrow gap between two side-by-side fixed bodies is investigated numerically in a two-dimensional (2D) numerical wave flume. The focus of the study is to examine the influence of incident wave frequency and inlet configuration of the gap on wave resonance behavior. It is found that the gap inlet configuration has significant effects on the resonant wave amplitude and frequency. The maximum resonant wave height in the gap is found to be as high as about 11 time of the incident wave height while the resonance frequency shifts to higher values at larger corner curvatures of the gap inlet. The physical mechanisms that are responsible for the influence of the inlet configuration on wave resonance are explained in light of the results of some controlled numerical tests. In addition, the geometrical properties of the fixed bodies, such as the body breadth, gap width and draft, are also found to have significant influence on gap resonance characteristics. Finally, an empirical model is proposed to predict wave resonance frequency for different curvatures of the gap inlet.