Based on the pressure potential differential (PPD) type gas laminar flow technology, a new type of laminar flow transducer is designed and tested. The flow transducer is composed of two components, i. e. main part and integrated cover plate. The shell of the transducer is machined from a block material, and capillary components are fixed in the two channels of the shell. There are internal embedded channels in the cover plate for pressure acquisition, which can replace outside pressure tubes. Other components, such as capillary components/ bundles, mesh filter, and pipe connector, are designed with the idea of modularity. The differential, absolute pressure sensors, and temperature sensor are integrated on the pressure acquisition cover plate. The principle of the PPD gas flow transducer is analyzed and the correction formula is given. Based on a piston gas flow standard device, the PPD laminar flow transducer was calibrated with air, and tested with air and nitrogen gases. The maximum flow rate is about 50 L/ min. The results show that, the flowrate measurement errors for the two kinds of gas are within ±0. 8%, and the turndown ratio is about 250. It is predicted that the PPD laminar flow transducer will be used in the micro & small gas flow measurement fields.