The carbonate reservoirs in the Ordovician Yijianfang Formation-Yingshan Formation of the Fuman Oilfield are typical fault-controlled fractured-cavity carbonate reservoirs. The well test analysis of single wells or interconnected units is challenging with three major difficulties: (1) The regimes of log–log curves are highly diverse, making well test model description difficult; (2) It is hard to determine the reservoir engineering parameters such as net thickness and porosity; (3) It is difficult to quantitatively determine the reservoir parameters such as permeability and cave volume. Based on well test data of more than 200 well times in the Fuman Oilfield, and by combining short-term well test data with long-term production history, this study classifies the reservoirs into four major categories (cave models, fracture models, pseudo-homogeneous models, and composite model) 1and sixteen subcategories, elucidates the characteristics of well test curves for each model, achieves the quantitative interpretation of wellbore storage factor and formation flow capacity, as well as qualitative description of reservoir dynamic characteristics in the Fuman Oilfield. It is important to note that the information obtained from the well test interpretation could be qualitative as well as quantitative. The well test interpretation results indicate that the wellbore storage factor and formation flow capacity are closely related to water injection effects; the cavity models have the highest wellbore storage factor and the best oil displacement effect by water injection; the composite model has the lowest wellbore storage factor and the poorest oil displacement effect by water injection. Based on the wellbore storage factor, water injection wells can be quickly optimized and the effects of water injection can be evaluated. The proposed method for well test analysis can provide reliable technical support for developing technical policies for such reservoirs and for enhancing oil recovery in the middle and later stages.