This study focused on gas/Newtonian and gas/non-Newtonian two-phase horizontal fluid flow behavior by analyzing their flow regime identification and flow structural analysis on a horizontal flow loop apparatus. This involved the recognition of two-phase flow regimes for this flow loop and validation with existing flow maps in the literature. In addition, the study included flow pattern identification via wavelet analysis for gas/Newtonian and gas/non-Newtonian two-phase fluid flow in a horizontal flow loop apparatus. Furthermore, the study was extended to the detailed examination of slug frequency in the presence of air/Newtonian and air/non-Newtonian fluid flow, and the predicted slug frequency model was applied to the studied systems. The obtained results suggest that the flow regime maps and slug frequency analysis have a significant impact. The obtained pressure sensor results indicate that the experimental setup could not provide high-frequency and high-resolution data; nevertheless, wavelet decomposition and wavelet norm entropy were calculated. It offered recognizable flow characteristics for bubble, bubble-elongated bubble, and slug flow patterns. Therefore, this study can provide deep insight into intricate multiphase flow patterns, and the wavelet could potentially be applied for flow analysis in oil and gas pipelines.