The Auckland-born coach has had previous coaching spells with Auckland Blues, New Zealand Maori and the Pacific Islanders.
Director of Rugby Dean Ryan said: "I am naturally delighted that Shane will be joining us at Warriors.
"Shane coaches players to have a real ambition to play and you only have to look at the back line development he has achieved this season at London Wasps to see his pedigree.
"He also has the ability to develop, support and bring through youngsters and that is crucial to the way I want Warriors to operate.
"Shane has a strong coaching background around the world, with Super 15 and international experience, and he will be a big asset to the coaching set-up at Warriors."