A thermosensitive lithographic printing plate comprising: a hydrophilic
support; a lower layer comprising a water-insoluble and alkali-soluble
resin; and an upper thermosensitive layer comprising a water-insoluble
and alkali-soluble resin and an infrared absorbing dye, whose dissolution
in an alkaline aqueous solution increases upon exposure, wherein a
surface of the upper thermosensitive layer has protrusions caused by
ununiformity of thickness of the upper thermosensitive layer in a
proportion of 0.1 or more and not more than 7 per .mu.m.sup.2 or the
upper thermosensitive layer comprises at least two alkali-soluble resins
having a different dissolution speed in an alkaline aqueous solution from
each other, and the at least two alkali-soluble resin cause phase
separation from each other.