We consider a finite difference scheme for the convective reaction-diffusion equation $u_t=u_{xx}+alpha(u^m)_x+u^{eta}, (0< x< 1,~ 0mgeqslant 1$ and $alpha>0$ are parameters. For many differential equations or systems the solutions can become unbounded in finite time $T$. Here the phenomena that is known as blow-up and the finite time $T$ is called the blow-up time. In this paper, we prove that the numerical blow-up time converges to the blow-up time with uniform temporal grid size.