X-ray spectra suitable for mammography, created by laser-based x-ray source at laser intensity about 1018 W/cm2, where investigated. The spectra consisted of a continuous bremsstrahlung emission and discrete K(alpha ), K(beta ) lines and have been obtained for Mo, Rh, Ag, In and Sn targets (Z equals 42, 45, 47, 49, and 50) with K(alpha ) emissions at 17.4, 20.2, 22.2, 24.2, and 25.3 keV, respectively. The continuous bremsstrahlung component extended to high energies with no cut-off energy. The shape of the continuous bremsstrahlung spectrum was described by the function E-p, where p (greater than 0) was primarily determined by the temperature of hot electrons produced in laser beam- target interaction. The absolute value of x-ray yield was proportional to the atomic number of the target Z. The intensity of characteristic x-rays was about a factor of five higher than the corresponding bremsstrahlung, and showed weak dependence (increase) when the atomic number of the target increased from Z equals 42 to Z equals 50.