Each custom record includes a Permissions subtab where you can restrict access by role to your custom records and the forms used to enter the records. Setting permissions within custom records themselves is the most flexible way to provide access to custom records.
Go to Setup > Other Setup > Record Types, and select a record type from the list.
On the Permissions subtab, choose a role and set the access level.
Repeat to provide access to additional roles, then Save.
You also can add the Custom Record Entries permission to a role, to provide users with that role access to all custom records.
Go to Setup > Users/Roles > User Management > Manage Roles (Administrator), and select a role from the list.
Click the Lists subtab, select Custom Record Entries from the dropdown list, set the access level, and click Save.
you make either of these changes, users may need to log out and log back in for the changes to take effect.
For more information about custom record permissions, see Setting Permissions for a Custom Record Type.