A pipe connection structure for an endoscope is provided with a pipe made
of a corrosion-resistant alloy material, and a piping block made of a
corrosion-resistant alloy material, the piping block having a pipe
insertion hole. An end of the pipe is fitted in the pipe insertion hole
and the pipe and the piping block are connected by welding by irradiating
a laser beam on the entire circumference of an area where the end of the
pipe is fitted in the hole formed on the piping block. An axial length of
the pipe inserted in the pipe insertion hole is in a range of 0.5 to 2
times a wall thickness of the pipe.