LiSr was produced in a heat-pipe oven and its thermal emission spectrum around 9300 cm^-1 was recorded by a high resolution Fourier transform spectrometer. In addition, selected lines of the spectrum of deeply bound vibrational levels of the 1^2Σ^+ and 2^2Σ^+ states were studied using laser excitation to facilitate the assignment of the lines. The ground state could be described for v^" = 0 - 2, N^" up to 105 and the 2^2Σ^+ state for v^' = 0 up to N^' = 68. For both states, Dunham coefficients,

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... spin-rotation parameters and potential energy curves were evaluated. A coupling of the 2^2Σ^+ state to the 1^2Π state was observed, allowing a local description with Dunham coefficients of the 1^2Π state and an approximate evaluation of the coupling strength.