This article presents a novel approach to measuring gas–liquid two-phase flow (GLTPF) using a throat-extended Venturi meter (TEVM) based on differential pressure (DP) ratios and fluctuations. The over-reading (OR) and mass quality are the dominant parameters for accurate mass flow rate measurement by a TEVM. First, a liquid OR model is established based on multiple DP ratios (DPRs), gas-to-liquid density ratio (GLDR), and liquid densitometric Froude number. This model is solved by integrating a deep neural network (DNN) with an iterative optimization technique. Subsequently, a mass quality model is developed based on multi-DP fluctuations and other related parameters, which can also be solved using a DNN. Finally, the liquid and gas mass flow rates are obtained sequentially from the preceding results. The proposed method addresses the issue of significant errors in the direct solution of the conventional dual-parameter measurements. It utilizes both the static and dynamic features of multi-DP to achieve the simultaneous measurement of gas and liquid mass flow rates using a single TEVM. The experiment was conducted within a gas flow rate range of $1.3\times 10^{-4} \sim 5.1\times 10^{-3}$ kg/s, and a liquid flow rate range of 1.12~3.95 kg/s. The results demonstrate that the relative error for liquid and gas mass flow rates is within ±3% and ±10%, respectively. This indicates that the proposed method is a cost-effective and viable solution for GLTPF metering using a TEVM, and it can be further adapted to other experimental conditions.