We establish weighted Bernstein inequalities in L p space for the doubling weight on the conic surface} as well as on the solid cone bounded by the conic surface and the hyperplane t = 1, which becomes a triangle on the plane when d = 1. While the inequalities for the derivatives in the t variable behave as expected, there are inequalities for the derivatives in the x variables that are stronger than what one may have expected.As an example, on the triangle {(x 1 , x 2 ) :The new inequality is stronger and points out a phenomenon unobserved hitherto for polygonal domains.