A method for manufacturing a semiconductor optical device comprising: epitaxially growing, on a growth substrate, a semiconductor lamination including a first semiconductor layer of a first conductivity type having a first surface, an active layer, and a second semiconductor layer of a second conductivity type opposite to the first conductivity type having a second surface, in this order; forming a second-conductivity-type-side electrode on said second surface; forming first isolation grooves from said second surface, penetrating through said second semiconductor layer and said active layer, and entering said first semiconductor layer, the first isolation grooves having a width becoming narrower with increase in depth; bonding a support body on said second-conductivity-type-side electrode; removing said growth substrate, thereby exposing said first surface of said first semiconductor layer; and forming a first-conductivity-type-side electrode on said exposed first surface; characterized by: separating said semiconductor lamination having said first-conductivity-type-side electrode and said second-conductivity-type-side electrode formed thereon from said support body; and dipping said semiconductor lamination having said first-conductivity-type-side electrode and said second-conductivity-type-side electrode formed thereon in a solvent, and applying ultrasonic waves, thereby separating said semiconductor lamination having said first-conductivity-type-side electrode and said second-conductivity-type-side electrode formed thereon at locations of said first isolation grooves. epitaxially growing, on a growth substrate, a semiconductor lamination including a first semiconductor layer of a first conductivity type having a first surface, an active layer, and a second semiconductor layer of a second conductivity type opposite to the first conductivity type having a second surface, in this order; forming a second-conductivity-type-side electrode on said second surface; forming first isolation grooves from said second surface, penetrating through said second semiconductor layer and said active layer, and entering said first semiconductor layer, the first isolation grooves having a width becoming narrower with increase in depth; bonding a support body on said second-conductivity-type-side electrode; removing said growth substrate, thereby exposing said first surface of said first semiconductor layer; and forming a first-conductivity-type-side electrode on said exposed first surface; characterized by: separating said semiconductor lamination having said first-conductivity-type-side electrode and said second-conductivity-type-side electrode formed thereon from said support body; and dipping said semiconductor lamination having said first-conductivity-type-side electrode and said second-conductivity-type-side electrode formed thereon in a solvent, and applying ultrasonic waves, thereby separating said semiconductor lamination having said first-conductivity-type-side electrode and said second-conductivity-type-side electrode formed thereon at locations of said first isolation grooves. separating said semiconductor lamination having said first-conductivity-type-side electrode and said second-conductivity-type-side electrode formed thereon from said support body; and dipping said semiconductor lamination having said first-conductivity-type-side electrode and said second-conductivity-type-side electrode formed thereon in a solvent, and applying ultrasonic waves, thereby separating said semiconductor lamination having said first-conductivity-type-side electrode and said second-conductivity-type-side electrode formed thereon at locations of said first isolation grooves.