Abstract: For application of joint factor analysis on the condition of multiple channels in text-independent speaker recognition, this paper proposes an eigenchannel space orthogonal combination method. The eigenchannel space can be estimated by a mix data method or a simple combination method on the condition of multiple channels. However, the former has space masking effects while the latter introduces space overlapping effects. This paper proves that the core computation of the speaker enrollment and test is an oblique projection. Space overlapping effects can be removed subsequently by an orthogonal method based on the above proof. On the NIST SRE 2008 core tasks corpus, the proposed method has a better performance than the mix data method and the simple combination method.