The invention relates to a production method of membrane diagnostic products. The membrane diagnostic products are membrane strips coated with a diagnostic reagent. The production method comprises the steps of: installing the membrane strips to be coated on a fixed platform frame of a sample application instrument, coating the membrane strips to be coated by using the sample application instrument, and taking down the well coated membrane strips after the completion of coating, wherein during installation of the membrane strips to be coated, a special sample application plate is adopted to install a plurality of membrane strips to be coated in one step, after the installation of both the membrane strips to be coated and the special sample application plate is completed, the sample application instrument is used to coat the plurality of membrane strips to be coated, installed on the special sample application plate, one by one until the plurality of membrane strips to be coated on the special sample application plate are coated completely, and then, the well coated membrane strips are taken down. According to the production method, the sample application instrument can be used to complete the sample application of a plurality of membrane strips to be coated in one step, so that the sample application efficiency is improved, meanwhile, the special sample application plate can be detachably arranged on the fixed platform frame, so that the replacement of the special sample application plate is facilitated, and a large amount of operation time is saved.