A light source apparatus comprising: an outer casing; a plurality of light source modules which (70/80) are disposed in said outer casing characterized in that each light source module include a light source member (1/2), a cooling body for cooling said light source member and a wind tunnel which is disposed in said outer casing and surrounds said cooling body of said light source module, the wind tunnel includes a first wind passage which allows cooling wind to pass through said cooling body of said light source module, wherein intake-openings through which cooling wind is taken into said outer casing from outside thereof are formed in a surface of said outer casing, one end of said first wind passage of said wind tunnel of each light source module is connected to one intake-opening, wherein the light source apparatus further comprises a duct disposed in said outer casing, connected to a discharge opening through which cooling wind passing through said cooling body of each light source module is discharged outside of said outer casing, is formed in said surface of said outer casing, connection openings through which a second wind passage in said duct and said first wind passage of said wind tunnel of each light source module are connected to each other, are formed in a surface of said duct, the other end of said first wind passage of said wind tunnel of each light source module is connected to one connection opening of said duct, and one end of said second wind passage of said duct is connected to said discharge opening of said outer casing, wherein a peripheral edge of said one end of said first wind passage of each light source module sur-rounds said intake-opening, said wind tunnel of each light source module includes a flange portion (10a/310a) on said peripheral edge of said one end of said first wind passage, a peripheral edge of the other end of said first wind passage of each light source module surrounds said connection opening, and said wind tunnel of each light source module includes a flange portion(10a/310a) on a peripheral edge of the other end of said first wind passage. an outer casing; a plurality of light source modules which (70/80) are disposed in said outer casing characterized in that each light source module include a light source member (1/2), a cooling body for cooling said light source member and a wind tunnel which is disposed in said outer casing and surrounds said cooling body of said light source module, the wind tunnel includes a first wind passage which allows cooling wind to pass through said cooling body of said light source module, wherein intake-openings through which cooling wind is taken into said outer casing from outside thereof are formed in a surface of said outer casing, one end of said first wind passage of said wind tunnel of each light source module is connected to one intake-opening, wherein the light source apparatus further comprises a duct disposed in said outer casing, connected to a discharge opening through which cooling wind passing through said cooling body of each light source module is discharged outside of said outer casing, is formed in said surface of said outer casing, connection openings through which a second wind passage in said duct and said first wind passage of said wind tunnel of each light source module are connected to each other, are formed in a surface of said duct, the other end of said first wind passage of said wind tunnel of each light source module is connected to one connection opening of said duct, and one end of said second wind passage of said duct is connected to said discharge opening of said outer casing, wherein a peripheral edge of said one end of said first wind passage of each light source module sur-rounds said intake-opening, said wind tunnel of each light source module includes a flange portion (10a/310a) on said peripheral edge of said one end of said first wind passage, a peripheral edge of the other end of said first wind passage of each light source module surrounds said connection opening, and said wind tunnel of each light source module includes a flange portion(10a/310a) on a peripheral edge of the other end of said first wind passage.