A method for producing a titanium plate by performing hot rolling on a titanium slab that is directly produced by using an electron beam re-melting process or a plasma arc melting process, comprising: when a face of the titanium slab to be rolled when the slab is subjected to hot rolling is defined as a " surface to be rolled ", and a face that is parallel to a rolling direction and is perpendicular to the surface to be rolled is defined as a "side surface", a step of melting at least one part of the side surface of the titanium slab in the vicinity of the surface to be rolled by radiating a beam or plasma toward the side surface without radiating a beam or plasma toward the surface to be rolled, and thereafter causing re-solidification to form a microstructure layer having an equivalent circular grain diameter of 1.5 mm or less to a position at a depth of at least 3.0 mm from a surface of the side surface in at least one part of the side surface; a step of performing a finishing process on the surface to be rolled of the titanium slab in which the microstructure layer is formed to bring X defined by formula below to 3.0 or less; and a step of subjecting the titanium slab after the finishing process to hot rolling under a condition in which L defined by below is 230 mm or more; X = largest value among H 0, H 1 and H 2 − smallest value among H 0, H 1 and H 2 L = R H 0 − H 3 1 / 2 where, the meaning of the symbols in the above formulae is as follows: X: slab flatness index H 0: thickness of a central part in a width direction of the titanium slab after the finishing process (mm) H 1: thickness of an end part (position at 1/8 of the width) in a width direction of the titanium slab after the finishing process (mm) H 2: thickness of an end part (position at 1/4 of the width) in a width direction of the titanium slab after the finishing process (mm) L: length of arc of contact of a roll in a first pass of rough rolling (mm) R: radius of a rolling roll in a first pass of rough rolling (mm) H 3: thickness of a central part in the width direction of the titanium slab on a delivery side in a first pass of rough rolling (mm). when a face of the titanium slab to be rolled when the slab is subjected to hot rolling is defined as a " surface to be rolled ", and a face that is parallel to a rolling direction and is perpendicular to the surface to be rolled is defined as a "side surface", a step of melting at least one part of the side surface of the titanium slab in the vicinity of the surface to be rolled by radiating a beam or plasma toward the side surface without radiating a beam or plasma toward the surface to be rolled, and thereafter causing re-solidification to form a microstructure layer having an equivalent circular grain diameter of 1.5 mm or less to a position at a depth of at least 3.0 mm from a surface of the side surface in at least one part of the side surface; a step of performing a finishing process on the surface to be rolled of the titanium slab in which the microstructure layer is formed to bring X defined by formula below to 3.0 or less; and a step of subjecting the titanium slab after the finishing process to hot rolling under a condition in which L defined by below is 230 mm or more; X = largest value among H 0, H 1 and H 2 − smallest value among H 0, H 1 and H 2 L = R H 0 − H 3 1 / 2 a step of melting at least one part of the side surface of the titanium slab in the vicinity of the surface to be rolled by radiating a beam or plasma toward the side surface without radiating a beam or plasma toward the surface to be rolled, and thereafter causing re-solidification to form a microstructure layer having an equivalent circular grain diameter of 1.5 mm or less to a position at a depth of at least 3.0 mm from a surface of the side surface in at least one part of the side surface; a step of performing a finishing process on the surface to be rolled of the titanium slab in which the microstructure layer is formed to bring X defined by formula below to 3.0 or less; and a step of subjecting the titanium slab after the finishing process to hot rolling under a condition in which L defined by below is 230 mm or more; where, the meaning of the symbols in the above formulae is as follows: X: slab flatness index H 0: thickness of a central part in a width direction of the titanium slab after the finishing process (mm) H 1: thickness of an end part (position at 1/8 of the width) in a width direction of the titanium slab after the finishing process (mm) H 2: thickness of an end part (position at 1/4 of the width) in a width direction of the titanium slab after the finishing process (mm) L: length of arc of contact of a roll in a first pass of rough rolling (mm) R: radius of a rolling roll in a first pass of rough rolling (mm) H 3: thickness of a central part in the width direction of the titanium slab on a delivery side in a first pass of rough rolling (mm). X: slab flatness index H 0: thickness of a central part in a width direction of the titanium slab after the finishing process (mm) H 1: thickness of an end part (position at 1/8 of the width) in a width direction of the titanium slab after the finishing process (mm) H 2: thickness of an end part (position at 1/4 of the width) in a width direction of the titanium slab after the finishing process (mm) L: length of arc of contact of a roll in a first pass of rough rolling (mm) R: radius of a rolling roll in a first pass of rough rolling (mm) H 3: thickness of a central part in the width direction of the titanium slab on a delivery side in a first pass of rough rolling (mm).