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To improve the hard tofu production in China and develop the utilization of okara(soybean residue), the effect of okara adding on the texture of tofu was investigated in this study. Okara was tried to be added to the soymilk for tofu-making. A kinugoshi (silken) tofu making way was employed in this study. Coagulants were 30 mM CaSO4, 30 mM GDL (glucono-delta-lactone), 15 mM CaSO4 + 15 mM GDL, 30 mM CaSO4 + 30 mM GDL, 60 mM CaSO4 and 60 mM GDL, respectively. Okara adding ratios (to soymilk volume) were 0, 5, 10, 15, 20 and 25% (w/v). Stress-strain, stress relaxation and creep behaviors of tofu samples were investigated. Stress relaxation and creep curves were found to be fit for 4-element Maxwell model and 4-element Burgers model, respectively. For CaSO4- coagulated tofu, the break stress of tofu increased initially with increasing the okara-adding ratio, then decreased and the parameters of the models for stress relaxation and creep showed similar trend. For GDL-coagulated tofu, the break stress decreased with increasing the okara adding ratio. Comparing with tofu only coagulated by CaSO4, the replacement of CaSO4 by GDL could improve the break stress of tofu. Both for CaSO4 and GDL, the increasing of coagulant amount resulted in large parameter values of simulated models. It was suggested that a proper okara-adding could strengthen the texture of CaSO4-tofu rather than weaken it. For producing hard CaSO4-coagulated tofu, adding proper ratio of okara, increase of coagulant amount and partial replacement with GDL could be alternatives.