Abstract: Three wave-guide rods including disc-rod, cap-rod and flexible rod were designed so as to test high/low-temperature vessels using ordinary AE sensors. For some special conditions, some support/fixed members protruded from insulation and welded to vessel shells can be directly used as wave-guide rods, and water-ice coupling can be adopted in AE testing of cryogenic monolayer vessels. A lot of field testing practice shows that those recommended wave-guide methods are economical, simple, and practical, they meet the needs of AE testing of most high/low-temperature vessels using ordinary sensors.