The minimum notice period and probation period we can give to employees in policy for start up company?

Can you please confirm the minimum notice period and probation period we can give to employees in policy for start up company? Can it be restricted for 3 days also?

For probation period you need not fix any NP. But after confirmation of services of the employee, you may fix NP by one month (for lower level of staff) and3 months NP for supervisors and above.
Similarly you can fix probation period by 6 months. Some companies will give probation period by 3 months only. Management can take a call on this.

It will depend on the nature of industry and its strength of employees/workmen in the organisation.

Dear Nidhi,
Beyond agreeing with Mr.Radha Krishna's views three days is no where applicable as handing over/taking over of responsibility involve some time. Replacement of an employee also takes time.