Apple - Stop sharing printer over WiFi

The User Manual has no documentation on any security features for that printer. So, regardless if it's WiFi or connected to Ethernet, it's a wide open printer on the network. Business class printers will have the ability to lock out users through a variety of methods - I always recommend these printers over the consumer ones for this (and many other reasons)

The "Printer Sharing" section on your Mac, is for printers connected to your Mac. It allows you to manage who/what can print to that printer via your Mac. Technically, you can share a networked printer, but as stated before, since that printer is "wide open," anyone can get to it regardless of the policies you configure on your Mac.

So, you have two options:

• create your own small Wireless network that only you have access to and put your printer on that.
• purchase a USB cable and connect your printer directly to your Mac.

(Option 2 is probably the most effective method).

As the existing answers have already mentioned - once connected to a network, any device on that network can print to it. It is not being controlled by your Mac's Sharing settings, it can be accessed directly by anyone on the network.

It appears from the manual that there are no additional security settings to define who may or may not use the printer. This is far more common in a business environment but your printer seems more oriented towards a consumer/family setup.

I think, practically, the solution may be to set the printer up to use WiFi Direct rather than connect it to the existing communal WiFi. This would allow you to specify your own new, separate password, effectively preventing others from accessing it, accidentally or intentionally, without that password.
Once set up, disable the regular WiFi connection to remove it from the existing network.

The instructions for setting up WiFi Direct start on page 47 of the linked manual.

You could, of course, set it up over USB, then your Mac's Sharing settings would indeed come into play - the downside of this would be the Mac would need to be switched on & awake for you to be able to print from any other device; your phone, for instance.

Your printer uses WiFi to connect to the local network. Any computer on the same network can then print to it directly, without 'going through' your Mac.

Even if your printer is off, it's likely that someone else's computer will hold the print job in a queue until the printer becomes available.

If you want to prevent that, then you need to look through the printer's manual to see what security features it has. Either that, or turn off the WiFi feature and use a USB cable.

Ultimately, this isn't a Mac software question.