This paper describes the design and characteristics of a submarine optical repeater housing subjected to field trials beginning in January, 1982, in Sagami Bay off the coast of Izu. Several new technologies were employed in the development of the housing: an efficient thermal-dispersing and shock-absorbing design employing Al powder-mixed rubber and He gas; an optical fiber feedthrough utilizing epoxy resin; and a cable coupling incorporating fiber slip prevention techniques. This repeater housing has been proven to be able to withstand payout and recovery operations onto and off of a 5000 m deep sea bed.