PURPOSE: To reduce the dial of a clinical thermometer and to enhance the manufacturing efficiency of a clinical thermometer when the clinical thermometer is manufactured.

CONSTITUTION: The clinical-thermometer manufacturing apparatus is provided with a chucking mechanism 11e by which a glass outer tube 10a into which a capillary 10b has been inserted is supported perpendicularly to its axial direction and with an image taking-in/processing means by which the inner-wall interval of a part to be used as a spherical part on the outer tube 10a supported by the chucking mechanism 11e is measured, thereby, a very small oval column is approximately calculated on the basis of its measured data and volume data to form the spherical part of a clinical thermometer is found. And also, the clinical-thermometer manufacturing apparatus is provided with a computer which decides melting point on the outer tube 10a according to the value of the volume data computed by the image taking-in/processing means, and a burner positioning means which supports a sealing burner so as to be freely movable and which moves the sealing burner to the fusing point on the outer tube 10a decided by the computer.