A four-block layout and its generation algorithm are proposed for the unconstrained two-dimensional plate guillotine cutting problem of rectangular items, in which the plate is divided into four blocks, and each block is arranged recursively. A row of the same kind of rectangular items is selected and placed in the left lower corner of the block. Along the upper and right boundaries of this row of rectangular items, the rest of the block is divided into two smaller sub blocks for further recursive investigation. Firstly, the recursive layout of rectangular items in all possible size blocks is generated using the dynamic programming algorithm at one time. Then the optimal four-block layout of rectangular items on the plate is determined using the implicit enumeration algorithm. The algorithm is compared with several typical literature algorithms using literature benchmark examples and random examples in accordance with the actual situation. The experimental results show that the time complexity of this algorithm is lower than or equal to the literature algorithm, and the value of layout is higher than that of the literature algorithm.