My Cat Found a Giant Cockroach in Our Japanese Home—What I’m Doing Before Next Summer

Sora had been staring at the living room ceiling for several minutes.

I called her name, but she did not even look at me. She just kept meowing at the same spot.

At first, I thought she had found a tiny moth or a spider. My three Bengal cats often notice insects long before I do, so this was not completely unusual.

Still, something about the way she refused to move made me curious.

I walked over, followed her eyes, and looked up.

That was when I froze.

There was a large cockroach clinging to the ceiling near the window.

I have lived in Japan for many years, but I still cannot get used to seeing cockroaches in summer. We do not see them often in our home—usually only once or twice a year—but every time one appears, it feels just as shocking as the first time.

And this one was not small.

It was big enough to make me stand there for a moment thinking only one thing:

Please do not fly.

My Cat Found a Cockroach on the Ceiling

Once I realized what Sora had been watching, I rushed to get the insect spray.

The cockroach was above us, close to the window, and I was terrified that it would disappear into the curtains or fly across the room.

I sprayed it several times until it finally fell to the floor.

Even then, I was too nervous to get close immediately.

I used several layers of kitchen paper to pick it up, sealed it inside a plastic bag, and then put that bag inside a second one. I tied both bags tightly before throwing them away.

Even after it was gone, I did not feel relaxed.

For the rest of the evening, I kept checking the ceiling, the curtains, the walls, and the spaces behind the furniture.

I knew it was probably over, but I still did not completely trust that there was only one.

Looking back, Sora probably noticed it long before I did.

Without her, the cockroach might have disappeared behind a cabinet before I even realized it was there.

Cockroaches in Japan Were a Surprise When I First Moved Here

When I first moved to Japan, I was surprised by how many cockroach products appeared in drugstores and home centers every summer.

There were sprays, traps, bait stations, outdoor products, and items designed for kitchens, entrances, balconies, and drains.

At the time, I remember wondering whether cockroaches were a serious problem in most Japanese homes.

After living here for years, I understand the reason for those large seasonal displays.

Japan’s hot and humid summers create good conditions for insects, and even a clean home can occasionally get an unwanted visitor from outside.

In our case, we usually see one large cockroach once or twice during the warmer months. Because they are large and appear infrequently, I suspect they may be entering from outdoors rather than breeding inside the house.

Still, seeing only one does not prove there are no others, so I do not want to ignore it completely.

How Cockroaches Can Get Inside Japanese Homes

This cockroach was on the ceiling near a window, which immediately made me wonder where it had entered.

We do not usually leave our windows open for long, and we use window screens. Even so, small gaps can appear depending on how a Japanese sliding window is opened.

This was something I did not understand when I first started living in Japan.

A screen can look closed while a narrow gap remains between the glass panel and the frame. Insects may also enter when the front door is opened, especially at night when indoor lights attract them.

Other possible entry points include:

gaps around air conditioner pipes
ventilation openings
drains
spaces under doors
cracks around windows
balcony doors

It is almost impossible to block every possible entrance, but checking these areas can reduce the chances of insects getting inside.

Since our cockroach appeared near the window, I plan to look more carefully at the screen, frame, and surrounding gaps.

The Cockroach Prevention I Use in Japan

Until now, my usual routine has been simple.

I see a cockroach, panic, and then go to the home center to buy new cockroach bait.

At this point, it has almost become an annual summer tradition.

But after this latest experience, I realized that I have been doing everything in the wrong order.

Buying cockroach prevention products after seeing one is already late.

The worst situation would be seeing a cockroach, leaving the house to buy supplies, and returning to find that it has disappeared.

That is not something I ever want to experience.

In Japan, one well-known option is Black Cap, a plastic bait station sold at home centers and drugstores. There are also many similar bait products from other brands.

I normally place this type of bait:

behind the refrigerator
under the kitchen sink
near the washing machine
close to the entrance
near the balcony door
around areas where pipes enter the home

For outdoor use, I would choose a product specifically labeled for outdoor placement. These should be placed somewhere sheltered, such as under an entrance roof, in a covered balcony corner, or near an outdoor air conditioner unit where they will not sit in standing water.

From now on, I plan to replace our bait before summer begins rather than waiting for the first sighting.

What Cat Owners Should Be Careful About

Because we live with three Bengal cats, I have to think about more than just killing insects.

My cats are curious, fast, and very interested in anything that moves.

If a cockroach falls to the floor, they may try to touch it, chase it, or put it in their mouths.

That means I need to move the cats away before using insect spray and keep them in another room until the area has been checked and cleaned.

I also make sure bait stations are placed where the cats cannot reach, roll, bite, or play with them.

Behind heavy appliances, inside a closed cabinet, or in another protected space is better than leaving them openly on the floor.

I do not assume that every product is automatically safe just because it comes in a plastic case. I check the package instructions and follow the warnings for homes with pets.

If spray lands on the floor or furniture, I also clean the area before allowing the cats back into the room.