We consider semiclassical computation of 3-point correlation functions of (BPS or non-BPS) string states represented by vertex operators carrying large charges in S 5 . We argue that the AdS 5 part of the construction of relevant semiclassical solution involves two basic ingredients: (i) configuration of three glued geodesics in AdS 2 suggested by Klose and McLoughlin in arXiv:1106.0495 and (ii) a particular Schwarz-Christoffel map of the 3-geodesic solution in cylindrical (τ, σ) domain into the complex plane with three marked points. This map is constructed using the expression for the AdS 2 string stress tensor which is uniquely determined by the 3 scaling dimensions ∆ i as noted by Janik and Wereszczynski in arXiv:1109.6262 (our solution, however, is different from theirs). We also find the S 5 part of the solution and thus the full expression for the semiclassical part of the 3-point correlator for several examples: extremal and non-extremal correlators of BPS states and a particular correlator of "small" circular spinning strings in S 3 ⊂ S 5 . We demonstrate that for the BPS correlators the results agree with the large charge limit of the corresponding supergravity and free gauge theory expressions. * e.buchbinder@imperial.ac.uk † Also at Lebedev Institute, Moscow. tseytlin@imperial.ac.uk