The spatiotemporal variation of soil penetration resistance (PR) and its response characteristics to seasonal drought were studied in order to reveal the disaster mechanism of seasonal drought. Combined with the determination of field and indoor, the spatiotemporal variations of PR was studied under four tillage measures, including deep tillage, conventional tillage, no-tillage and compaction for the summer maize. During the mild and moderate drought, the PR of three tillage measures surpassed the maximum resistance suitable for the root (2.0 MPa) except deep tillage. Soil PR showed unimodal distribution in 0–40 cm soil layer, and the size and position of the peaks were different among tillage measures. With the increase of soil water content, the size decreased and the position went down in soil layer. Soil PR had good response to seasonal drought. The correlation between soil PR and water content was non-linear and negative significantly, with the correlation coefficient of –0.839 and binomial formula. There was a critical response, when seasonal drought reached a certain degree, the violent change of soil PR was caused by water content changed finely. Soil PR was an unneglectable factor in seasonal drought, and the effect of high penetration resistance due to lowered water content on crops must be considered.