In this paper, a novel Yb metal–organic frameworks {[Yb(L)(DMA)(H2O)]·(3H2O)}n (Yb‐MOF, H3L is 4‐(N,N′‐bis(4‐carboxylbenzyl)amino)benzenesulfonic acid) was synthesized by solvothermal reaction. Modified Yb‐MOF was prepared by the potassium permanganate method for removing the Cu(II) and As(V) from simulated wastewater. The optimal pH value of modified Yb‐MOF for Cu(II) and As(V) adsorption was 5, and the optimal dosage of adsorbent was 0.04 mg/10 ml by static adsorption test. Four isothermal adsorption models (Freundlich, Langmuir, Temkin, and Dubinin–Radushkevich models) were fitted and analyzed. The adsorption processes of Cu(II) and As(V) were consistent with Freundlich, Langmuir, and Temkin models. The highest Cu(II) and As(V) adsorption capacity are 59.418 and 81.169 mg/g, respectively. The adsorption kinetic model and thermodynamic analysis of the modified Yb‐MOF for Cu(II) and As(V) were studied. The results showed revealed that the pseudo‐second‐order kinetic had a higher correlation association with the Cu(II) and As(V) adsorption process, indicating that chemisorption was dominant in both processes. At 298 and 308 K, the Cu(II) and As(V) adsorption by modified Yb‐MOF is spontaneous.