The investigation of the infection rate of domestic apple orchards by four types of apple viruses (Apple chlorotic leaf spot virus [ACLSV], Apple stem pitting virus [ASPV], Apple stem grooving virus [ASGV], Apple mosaic virus [ApMV]) and one type of viroid (Apple scar skin viroid, ASSVd) found that most apple trees were infected with viruses and viroid at the rate of 97.3%. By region, the infection rate in Jeongseon stood at 98.8%, Danyang at 100%, Yesan at 100%, Jangsu at 89.1%, and Muju at 98.1%. By each virus and viroid, the infection rate of ASGV was the highest at 93.4%, followed by ASPV at 85.7%, ACLSV at 59.0%, ASSVd at 6.7%, and ApMV at the lowest 3.6%. In addition, 84.8% of the cases were infected with two or more types of viruses and viroid, nearly seven times the single type infection rate of 12.4%, and the cases infected with three viruses, ASPV, ACLSV, and ASGV accounted for 56.2%, more than the half the total number of trees investigated.