Objective To explore the changing levels of serumIL-17 and Dectin-1 and their implication in non-neutropenic pa-tients with invasive pulmonary aspergillosis (IPA).Methods The clinical data were reviewed for 23 non-neutropenic patients with clinical diagnosis of IPA (IPA group),31 patients with clinical diagnosis of pneumonia (pneumonia group)and 51 healthy subjects(control group).The peripheral serum was collected to analyze IL-17 level by ELISA.Serum Dectin-1 level was also determined at the same time.Serum G test,GM test,WBC and CRP level were also assayed for the patients in IPA group.Pa-tient outcome was followed up and analyzed in terms of serum IL-17.Results The serum IL-17 level of the patients in IPA group was significantly higher than that in the control group (P <0.05).The serum IL-17 level in the pneumonia group was not significantly different from that in the control group (P >0.05).The serum Dectin-1 level in IPA group was significantly higher than that in the control group (P <0.05).For the patients in IPA group,serum IL-17 level was positively correlated to serum Dectin-1 level (r=0.81 ,P <0.05),while serum IL-17 and Dectin-1 levels were not correlated to the results of G test, GM test, WBC,CRP or patient outcome (P > 0.05 ). Conclusions Dectin-1 may be produced and Th17 cell immunity activated in response to Aspergillus fumigatus in-fection in non-neutropenic patients.And,serum Dectin-1 level is correlated with Th17 response.