Background Patients receiving moderate emetic risk chemotherapy (MEC) occurs chemotherapy-induced nausea and vomiting (CINV) in 30–90%, however the optimal antiemetic treatment remains controversial. Methods In this multicenter, prospective, observational study of adults treated with MEC for various cancer types in Japan, We enrolled patients kept diaries documenting CINV. All participants received a 5-HT3 receptor antagonist(5HT3RAs) and dexamethasone. We assessed various possible risk factors for complete response (CR; no emetic events and no antiemetic measures), total control (TC; no emetic events , no antiemetic measures and no nausea) and complete control (CC; no emetic events, no antiemetic measures and less than mild nausea) by univariate and multivariate analysis. Results Of the 400 patients enrolled from May 2013 to January 2015, 386 were eligible for evaluation. The overall CR rate was 64%, CBDCA-based chemotherapy and oxaliplatin-based chemotherapy were particularly low. However, we showed that the CR rates in men were high in CBDCA(AUC5)+ETP (80%), CapeOX (78%) and CBDCA+PTX for lung cancer(73% ). Emesis occurred significantly more women (30%) than men (16%) of patients overall. TC and CC were achieved by 51% and 61% of patients. Logistic regression analysis revealed that age <65 years and history of motion sickness or pregnancy-associated vomiting were risk factors for nausea and being women for vomiting. Conclusions Our data support triplet regimen including NK1 receptor antagonist with woman receiving CBDCA-based chemotherapy or oxaliplatin-based chemotherapy. However, it became clear that two antiemetics for men received CBDCA(AUC5)+ETP, CBDCA+PTX for lung cancer and CAPOX may be sufficiently effective. Further individualization of antiemetic regimens for patients receiving MEC on the basis of both type of chemotherapy regimen and sex is needed.