Castor bean (Ricinus communis L.) is important an important plant due to its easily cultivation, drought tolerance and beneficial adaptation combined to other food crops, like peanuts (Arachis hypogaea L.). Castor is an interesting option to increase producer income and improve land use efficiency in intercropping. This research was carried out to evaluate advantages, yield, cost of production and profitability in the intercropping castor/peanut as a function of sowing time. The castor genotype (BRS Energia) and peanut (BR-1) were grown in monocropping and intercropping systems. A randomized block design was used with four replications and eight treatments, being five treatments in intercropping (castor + peanut) varying the interval sowing of peanut regarding to the sowing of castor (0, 10, 15, 20 and 25 days), and three treatments with castor and peanut cultivated in monocropping. The yield of both crops as well the profitability of the cropping systems, cost of production and competitive rates were evaluated. The grain yield of both intercropped crops was affected when the sowing time was expanded. There was better castor yield in longer sowing time compared to peanut. In this case, intercropping was more advantageous to castorbean when peanut was sown between 15 and 20 days late with better competitive ability of castor. The larger total operational cost of US$ 1452.11 ha -1 observed in peanut monocropping spaced 1.0 m × 0.2 m mainly due to higher material expenses and inputs, compared to intercropped system. The intercropping castor/peanut in the spaces 2.0 × 0.5 (castor) and 2.0 × 0.2 (peanut) under Brazilian semiarid region can be suitable and profitable when peanut is sown 20 days after castor.