Paper-based assays such as lateral flow assays are good candidates for portable diagnostic owing to their user-friendly format and low cost. In terms of analytical detection, the lateral flow assays usually require dedicated instruments to obtain quantitative results. Here we demonstrate a lateral flow assay with handheld pressure meter readout for rapid detection of disease-related protein with high sensitivity and selectivity. Based on the pressure change produced by the catalytic reaction of Pt nanoparticles related to the concentrations of the target, a quantitative reaction platform was established. During the lateral flow assay, the Pt nanoparticles are aggregated in the test line to form a gray band by biomolecular recognition, and finally convert recognition signal into highly sensitive pressure readout for quantitative analysis. Without sophisticated instrumentation and complicated operations, the whole detection process can be completed within 20 minutes. The limit of detection for myoglobin (2.9 ng/mL in diluted serum samples) meets the requirements of clinical monitoring. With the advantages of low cost, easy operation, high sensitivity and selectivity, the method represents a versatile platform for point-of-care testing of disease biomarkers.