: The secure gripping of soft grippers remains a difficult challenge to address. To solve this challenge, the Single-axis deformation (SD) soft grippers were designed that were inspired by the blooming behavior of petunias. Four SD finger structures were designed by analyzing the anatomical structure of petunia petals. The stress concentration resulting from the deformation of the fingers with different structures was analyzed using numerical methods under the same deformation load conditions. In order to prove the SD soft grippers have a improving ability of secure gripping, The dexterity, gripping capacity, and radial load-bearing capacity of the SD soft grippers were tested through experiments. The experimental results shown that the opening and closing range of the SD soft gripper is 18mm-144mm, the maximum gripping load is 39.4N, and the radial bending angle is only 2.76 when the radial load is 24N.