Yes but you must be careful to make sure that the specifications you have match.
Many companies are increasingly replacing brushed DC motors with brushless DC motors in a wide range of systems but swapping to steppers is less common.
What is more common is to replace geared brushed DC motors with a stepper motor in applications such as pumps, lab equipment and similar applications where positional accuracy can be improved vastly by using a stepper motor and stepper motor controller.
The key to making the transition between the two units successful is making sure you know the performance characteristics and key specifications of the motor that you are wanting to replace and then being able to make an appropriate match with a stepper motor. If you are not sure how to find out the performance characteristics of the motor (and gearbox) that you have you can start with the part number of the motor and research that. Key characteristics to look for are max and nominal RPM and torque.
Also bear in mind that the physical size of the motor might be important to your application. Please let us know if this is important to you.
If you are still not sure what is best you can always CONTACT US and we will be more than happy to help.