Borrowing a technique due to Ando-Li-Mathias, we define a geometric mean of (k + 1) (positive invertible) operators from that of k (or a k-tuple of) operators with a parameter λ ∈ (0, 1]. If λ = 1, then the corresponding geometric mean G λ (= G 1 ) of (k + 1) operators is one defined by Ando-Li-Mathias, and if λ = 2/3, then G λ is one given by one of the authors in the preceding paper. We also show that a formula due to Yamazaki of the geometric mean for a 3-tuple of 2 × 2 matrices satisfying a

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... trace condition does not depend on any choice of a parameter in construction.