A floor scrubber is a floor cleaning device. It can be a simple tool such as a floor mop or floor brush, or in the form of a walk-behind or a ride-on machine to clean larger areas by injecting water with cleaning solution, scrubbing, and lifting the residue off the floor. With advancements in robotics, autonomous floor-scrubbing robots are available as well.

Automatic floor scrubbers, also known as auto scrubbers, are a type of floor cleaning machine that are used to scrub a floor clean of light debris, dust, oil, grease or floor marks. These machines have either a rotary (disk) or cylindrical scrubbing head and an automated system for dispensing cleaning solution and then vacuuming it up. So, in one pass over the floor, a user can dispense a cleaning agent, scrub it into the floor, then vacuum it all up with an autoscrubber squeegee attached at the back of the machine. Auto scrubbers have a separate dispensing (solution) tank and collection (recovery) tank to keep the clean water separate from the dirty water and can be categorized into one of three main types: walk behind, stand-on, and rider.

Floor scrubbers are a more hygienic alternative to traditional cleaning methods such as a mop and bucket. Environmentally safe soaps can be used in conjunction with a reduced water system to save on both the amount of chemicals released into the environment as well as the amount of gray water produced. Some scrubbers are even capable of cleaning without a water and chemical system at all.

Most autoscrubbers cannot reach edges, corners, clean under obstructions such as drinking fountains, and cannot fit into alcoves. Therefore, mopping is needed to clean areas the autoscrubber cannot reach. Some manufacturers now produce floor scrubbers with orbital or oscillating brush decks, allowing edges, corners and overhangs to be fully cleaned.

Modern floor scrubbers have a pre-sweep option that removes the need to sweep the floor before scrubbing. The pre-sweep brush head is placed in front of the vacuum system to collect dust and debris before it can block the vacuum system. In the past it was important to sweep the floor before scrubbing to remove any debris and dust that could clog the vacuum hose or build up in the vacuum motor, which can decrease performance. If this happens, the hose may need to be removed to clear the obstruction and/or the motor may need to be blown out with compressed air.

Stripping solution should never be used as it can cause damage to the solution dispensing system, but can still be vacuumed up by the machine without harm. Occasionally, the solution system should be flushed with water mixed with vinegar to remove any soap and calcium deposits that could build in the solution system.

After each use, the dispensing (solution) and especially the collection (recovery) tanks should be emptied and rinsed out to prevent dirt build up. The pads/brushes, vacuum hose, and squeegee should also be rinsed to prevent dirt buildup. The motor should be run for several minutes afterwards to remove any moisture that could be present in the motor to reduce chances of corrosion that could damage the vac motor. Failure to do this maintenance can result in a loss of vacuum airflow and increase in costly repairs.

There are three common types of automatic floor scrubber heads: disk, cylindrical, and square oscillating.