The spectrum of singly ionized molybdenum has been recorded with Fourier transform spectrometers in the wavelength interval 1500–7000 Å. We report improved energy values for a total of 330 levels, 153 even and 177 odd, which belong to the 4d5, 4d45s, 4d35s2, 4d46s, 4d45d, 4d45p and 4d35s5p configurations. 110 of the levels have been found in the present analysis. We have also present calculated eigenvector components and oscillator strengths.