A droplet volume detection device and method and a droplet volume adjusting method for improving conveniences of adjustment and measurement and reducing measurement error. The detection device (100) comprises at least one measurement unit (11), each measurement unit (11) comprising a first measurement groove (111), at least one second measurement groove (112), and a third measurement groove (113) adjacent to the second measurement groove (112). The volume of the first measurement groove (111) is greater than the total volume of all second measurement grooves (112); the height of a sidewall (114) shared by the first measurement groove (111) and the adjacent second measurement groove (112) is less than the height of a sidewall of the side, where no second measurement groove (112) is provided, of the first measurement groove (111); the height of a sidewall (115) shared by the second measurement groove (112) and the adjacent third measurement groove (113) is less than the height of a sidewall of the side, where no third measurement groove (113) is provided, of the second measurement groove (112) and the height of a sidewall where no first measurement groove (111) is provided; and the height of the sidewall (115) shared by the second measurement groove (112) and the adjacent third measurement groove (113) is less than the height of a sidewall of the side, where no second measurement groove (112) is provided, of the first measurement groove (111).