The invention discloses a low negative pressure ignition control device and method. The control device comprises a sintering machine trolley, a first air bellow and a second air bellow, wherein the first air bellow and the second air bellow are arranged below the sintering machine trolley. The first air bellow is located under an igniter of a sintering machine. The first air bellow and the second air bellow are each connected with an air bellow bent pipe. The air bellow bent pipes are each connected with an air bellow vertical pipe. An electric butterfly valve is arranged on each air bellow bent pipe. A baffle plate with the cross section and the longitudinal section both in a wedge shape is arranged in the first air bellow. According to the control method, the low negative pressure ignition control device is utilized for achieving control over the negative pressure in a hearth of an ignition furnace. In the low negative pressure ignition control device and method, the baffle plate is combined with adjustment of the opening degrees of the electric butterfly valves, flexible adjustment of the negative pressure in the hearth of the ignition furnace can be achieved, and coal gas consumption can be reduced. According to the negative pressure ignition control device, the negative pressure of the ignition air bellows and the negative pressure of the hearth can be flexibly and effectively controlled, normal proceeding of the sintering process is kept, ignition energy consumption is reduced, the structure is simple, and cost is low.