Paper-based electrochemical biosensors are a promising alternative to conventional biosensors. Herein, a screen-printed paper-based electrochemical flow biosensor was developed. The sensor comprised carbon-based working and counter electrodes and an Ag/AgCl reference electrode that was printed directly on paper, thereby forming a flow path. Glucose oxidase (GOx) was immobilized on polystyrene (PS) beads and a mediator tetrathiafulvalene was introduced upstream of the electrodes. The response current of the biosensor increased linearly with the glucose concentration, up to 100mM of glucose.