To provide a non-contact type mechanical seal which can exert good sealing function specified by the design in accordance with the given conditions including the seal structure and which can be easily designed and fabricated.

The second seal ring 24 is formed from a seal ring body 241 made of carbon and a silicon carbide film 242 formed as covering part of the body 241. The surface of the film 242 is formed in the second sealing end face 24a to constitute a ring-shaped plane parallel with the first sealing end face 22a on low pressure conditions where no pressure strain is generated (see Fig. A). The thickness T of the silicon carbide film 242 is set so that the second sealing end face 24a is elastically deformed to a ring-shaped taper surface capable of forming a ring-shaped space 27 having a wedge-shaped section gradually narrowing in the non-seal fluid region A2 in the area to the first sealing end face 22a because of the interference of the elastic strain in the silicon carbide film 242 with the pressure strain in the ring body 241 on high pressure conditions where pressure strain is generated (see Fig. B).