This paper investigates the influence of production-logging tool on wellbore flow-rate and pressure measurements. The focus of the investigation is on the disturbance caused by the production-logging tool and the coiled tubing on the original flow conditions in the wellbore. An analytical model is used in the investigation and single-phase liquid flow is assumed. The influence of the production-logging tool on the measurements is substantiated by the deviation from the original flow-rate and pressure profiles. It is shown that the influence of the production-logging tool manifests itself in low-conductivity wellbores. High production rates further amplify the effect of the production-logging tool. It is concluded that the effect of the production-logging tool may be ignored if dimensionless well conductivity exceeds 500 and the Reynolds number is lower than 100000. Results indicate that a production log run in a low-conductivity horizontal well may not indicate the low-permeability zones along the well.