We report to obtain dual-species Bose-Einstein condensates (BECs) of 39K-87Rb mixture in the hyperfine ground states F=1,mF=-1. Since the background scattering length of 39K is negative, we must manipulate the scattering length by Feshbach resonance to realize forced evaporative cooling of 39K. We measure the homonuclear and heteronuclear Feshbach resonance and determine the scattering strength in their hyperfine ground states |1,-1? at magnetic fields between 0 and 200 G. Two broad s-wave Feshbach resonances at 32.6 G and 162.8 G in the |1,-1? state induce the positive intraspecies scattering length of 39K in the region between them. Within this window, the interspecies scattering length of 39K-87Rb can be tuned by an s-wave Feshbach resonance at 117.6 G. We further compare the different magnetic field regions for the efficiency of evaporation cooling of 39K-87Rb mixture by optimizing the intraspecies and interspecies interactions. At last, we obtain the maximum dual-species BECs in the |1,-1? state at 117.8 G with the background repulsive interspecies scattering length aK～11a0 and the intraspecies scattering aRbK～286a0. This platform provides the opportunity to study quantum droplets.