A lighting device for vehicles, such as a headlight or a headlamp, comprising a cup-shaped housing body designed to be mounted on a vehicle body and at least one rotating lighting module arranged within the housing body facing a front inlet opening thereof closed by a transparent cover or lens; each rotating lighting module comprising at least one light source and a movable optical unit borne by a support arranged within the housing body, the movable optical unit being rotating in relation to the at least one light source around at least a first axis and being operatively associated to the at least one light source; the transparent cover or lens having a peripheral rim facing the housing body and coupling within a channel-shaped seat provided along a front peripheral rim of the housing body delimiting said inlet opening thereof, an adhesive sealing thread being applied within said channel-shaped seat; said device being characterized in that it further comprises a protective shield arranged solely at a bottom wall of the housing body and between the housing body and the transparent cover or lens, the protective shield being designed so as to run along at least part of a bottom profile of the inlet opening facing the at least one rotating lighting module; said protective shield having a first rim projecting upwards in front of the transparent cover or lens and arranged between the transparent cover or lens and at least part of said support and/or of a bottom section of the movable optical unit; i)- the protective shield extending in cantilever fashion from the inlet opening, projecting forward thereof, at least in part beyond a bottom rim of the inlet opening, transversally said bottom rim thereof and within an inner concavity of the transparent cover or lens, which is cup-shaped; ii)- the protective shield having in a transversal cross-section, taken along an optical axis of the at least one rotating lighting module, a substantially L-shape defined by a bottom wall and by a front wall thereof, the front wall defining said first rim projecting upwards of the protective shield, said first rim projecting upwards being configured such that iii)- said protective shield is always interposed between iv)- said at least part of said support and/or of a bottom section of the movable optical unit of said at least one rotating lighting module; and v)- both a bottom portion of the peripheral rim of the transparent cover or lens and said bottom rim of the inlet opening of said body, axially beyond both of them along the optical axis of each at least one rotating lighting module, vi)- such as said protective shield is arranged always interposed between the interior of the housing body and the adhesive sealing thread applied within said channel-shaped seat, at least at a part thereof facing the bottom sections of the movable optical unit of the at least one lighting module, so avoiding any risk that part of the adhesive sealing thread may reach, the at least one lighting module. i)- the protective shield extending in cantilever fashion from the inlet opening, projecting forward thereof, at least in part beyond a bottom rim of the inlet opening, transversally said bottom rim thereof and within an inner concavity of the transparent cover or lens, which is cup-shaped; ii)- the protective shield having in a transversal cross-section, taken along an optical axis of the at least one rotating lighting module, a substantially L-shape defined by a bottom wall and by a front wall thereof, the front wall defining said first rim projecting upwards of the protective shield, said first rim projecting upwards being configured such that iii)- said protective shield is always interposed between iv)- said at least part of said support and/or of a bottom section of the movable optical unit of said at least one rotating lighting module; and v)- both a bottom portion of the peripheral rim of the transparent cover or lens and said bottom rim of the inlet opening of said body, axially beyond both of them along the optical axis of each at least one rotating lighting module, vi)- such as said protective shield is arranged always interposed between the interior of the housing body and the adhesive sealing thread applied within said channel-shaped seat, at least at a part thereof facing the bottom sections of the movable optical unit of the at least one lighting module, so avoiding any risk that part of the adhesive sealing thread may reach, the at least one lighting module.