Crystalline form I of (R, E) -N- (4- (3-chloro-4- (pyridin-2-ylmethoxy) -phenylamino) -3-cyano-7-ethoxyquinolin-6-yl) -3 dimaleate (1-methylpyrrolidin-2-yl) acrylamide, characterized in that Cu Kα radiation is used to obtain the X-ray diffraction patterns represented by 2θ angles and interplanar crystal distance, the crystal having X-ray diffraction patterns as shown in Figure 1 in which there are characteristic peaks in 6.28 (14.06), 6.74 (13.10), 10.60 (8.34), 11.58 (7.64), 13, 50 (6.55), 14.90 (5.94), 15.80 (5.60), 18.26 (4.85), 20.66 (4.30), 21.14 (4.20 ), 22.96 (3.87), 24.34 (3.65), 25.54 (3.49) and 26.12 (3.41).Forma cristalina I de dimaleato de (R,E)-N-(4-(3-cloro-4-(piridin-2-ilmetoxi)-fenilamino)-3-ciano-7-etoxiquinolin-6-il)- 3-(1-metilpirrolidin-2-il)acrilamida, caracterizada por que se usa radiación Kα de Cu para obtener los patrones de difracción de rayos X representados por ángulos 2θ y distancia de cristal interplanar, teniendo el cristal patrones de difracción de rayos X como se muestra en la Figura 1 en la que hay picos característicos en 6,28(14,06), 6,74(13,10), 10,60(8,34), 11,58(7,64), 13,50(6,55), 14,90(5,94), 15,80(5,60), 18,26(4,85), 20,66(4,30), 21,14(4,20), 22,96(3,87), 24,34(3,65), 25,54(3,49) y 26,12(3,41).