In this paper we establish a Serrin-type regularity criterion on the gradient of pressure for the weak solutions to the Navier-Stokes equations in
R
3
\mathbb {R}^3
. It is proved that if the gradient of pressure belongs to
L
α
,
γ
L^{\alpha ,\gamma }
with
2
/
α
+
3
/
γ
≤
3
2/\alpha +3/\gamma \leq 3
,
1
≤
γ
≤
∞
1\leq \gamma \leq \infty
, then the weak solution is actually regular. Moreover, we give a much simpler proof of the regularity criterion on the pressure, which was showed recently by Berselli and Galdi (Proc. Amer. Math. Soc. 130 (2002), no. 12, 3585–3595).