The invention relates to a water turbine, provides a method for estimating basic parameters of a mixed-flow type water turbine, and aims to estimate the basic parameters of the mixed-flow type water turbine. The basic parameters to be estimated of the water turbine comprise a specific speed ns, a unit speed n11 and unit flow Q11. The method comprises the following steps: determining the specific speed of the mixed-flow type water turbine to be estimated, and recording the specific speed as ns; determining the maximum application water head of the mixed-flow type water turbine to be estimated, recording the maximum application water head as Hmax, and judging a range where the Hmax falls; estimating the basic parameters according to estimation formulas of the corresponding ranges of Hmax, wherein the formulas are as follows: when Hmax is less than or equal to 100 m, ns=374.05e<-0.0053Hr>, n11=45.395e<0.0022ns> and Q11=5.9 x 10<-3> x ns<0.9516>; when Hmax is greater than 100 m and less than or equal to 200 m, ns=2191.5Hr<-0.5007>, n11=48.289e<0.002ns> and Q11=1.0642Ln(ns)-4.7812; when Hmax is greater than 200 m and less than or equal to 300 m, ns=343.12e<-0.0042Hr>, n11=1.2874ns<0.7878> and Q11=0.7821Ln(ns)-3.3718; when Hmax is greater than 300 m, ns=3609.2Hr<-0.6189>,n11=37.207ns<0.1186> and Q11=0.3652Ln(ns)-1.4009. The method is applicable to the mixed-flow type water turbine and can better meet new hydropower engineering requirements.