Surindar Kumar Trehan (S.K. Trehan) is an Indian mathematician who specialised in Non-linear stability in magnetohydrodynamics.He was awarded in 1976 the Shanti Swarup Bhatnagar Prize for Science and Technology, the highest science award in India, in the mathematical sciences category. Prof. Trehan has done significant work on stability of force-free magnetic fields, stability ofjets and cylinders and stability of inhomogeneous plasmas.