Background. De novo posttransplant malignancy (PTM) is a serious complication of transplantation. Incidences may vary among solid organ transplantations (SOTs) and may take to particular screening recommendations and posttransplantation care. Methods. Adult recipients, from the U.S. Organ Procurement Transplant Network/United Network for Organ Sharing database (data as of September 3, 2010), of a primary kidney transplantation (KT), liver transplantation (LT), heart transplantation (HT) or lung transplantation (LuT) performed in the United States between 1999 and 2008 were selected. Multiple-organ recipients and those whose grafts failed within 2 weeks after transplantation were excluded. The incidence of PTM (in 1000 person-years) was estimated using the Kaplan-Meier product-limit method and compared with SOT and the general population. Results. The cohort included 193,905 recipients (123,380 KT; 43,106 LT; 16511 HT; and 10,908 LuT). PTM incidence was 8.03, 11.0, 14.3, and 19.8 in KT, LT, HT, and LuT, respectively. In general, PTM recipients were 3 to 5 years older, mostly whites, and are males in all SOTs. In KT, the type of cancer with the highest incidence was posttransplant lymphoproliferative disorder (PTLD, 1.58%), followed by lung (1.12%), prostate (0.82%), and kidney (0.79%) cancers; in LT, PTLD (2.44%), lung and bronchial (2.18%), primary hepatic (0.91%), and prostate (0.88%) cancers; in HT, lung and bronchial (3.24%) and prostate (3.07%) cancers, and PTLD (2.24%); and in LuT, lung and bronchial cancers (5.94%), PTLD (5.72%), and colorectal cancer (1.38%). PTLD, Kaposi sarcoma, and lung and bronchial cancers were increased in all SOTs, when compared with an older (55- to 59-year-old) population. Conclusions. Cancer incidence is different among solid organ transplantations, and ratios may be higher than those in the 55-to 59-year-old population.