The spatial distribution of high-order harmonic generation from H+2 molecules is theoretically investigated. Results show that the molecular harmonic emission mainly occurs around two H nuclei. When the internuclear distance is relatively small, the harmonic intensities of the two H nuclei are almost the same. The harmonic intensity emitted by the positive-H nucleus is higher than that of the negative-H nucleus with the internuclear distance increasing. With the introduction of the spatial inhomogeneous laser field, the harmonic intensity emitted by the negative-H nucleus is slightly higher than that of the positive-H nucleus when the internuclear distance of H+2 molecules is relatively small. The harmonic intensity emitted by the positive-H nucleus is higher than that of the negative-H nucleus when the internuclear distance is larger. As the spatial position of the space inhomogeneous laser field shifts from negative to positive(from －100 a.u. to 100 a.u.), the harmonic intensity emitted by the positive-H nucleus decreases gradually. The ultrashort attosecond pulses with durations of 66 as and 62 as can be obtained by superposition of harmonics.