In this paper, we consider $$L^p$$
L
p
- estimate for a class of oscillatory integral operators satisfying the Carleson–Sjölin conditions with further convex and straight assumptions. As applications, the multiplier problem related to a general class of hypersurfaces with nonvanishing Gaussian curvature, local smoothing estimates for the fractional Schrödinger equation and the sharp resolvent estimates outside of the uniform boundedness range are discussed.