Tunable laser spectroscopy measurements on low‐pressure gases have been performed using magnetic‐field‐tuned lead‐salt semiconductor diode lasers in the 4‐ to 7‐&mgr;m region. Use of magnetic field tuning in conjunction with the conventional current tuning is shown to significantly increase the versatility of diode lasers in high‐resolution spectroscopy. Details of the tuning characteristics for fields up to 90 kG are presented.