Budget
Aster Plaza
City convention center with guest rooms on top two floors. Cable Internet access in rooms, coin-fed access available in lounges, coin laundry facilities on 7th floor. Front door locked at midnight.
K's House
Part of the popular hostel chain. No curfew or lockout, free wifi, computers with Internet access available in the lobby for a small fee, and laundry facilities. Take the south exit from JR Hiroshima Station, then follow the tram tracks across the river. When they split, follow the tracks that go along the river, and look down the streets to your right. You should see a large K's House sign.
Hana Hostel
A comfortable hostel. Every private room has a bathroom or a toilet/washstand. They offer free wifi with your laptop ¥100 per 30 min for hostel computers, and rental bikes at ¥500 per day. There's no curfew or lockout, and they're willing to hold luggage early or after check-out.
For a short night before an early train, the cheapest digs in town will be to nap in the easy chairs at the two Internet cafes outside the south exit of JR Hiroshima Station see Contact, or possibly a Nagarekawa karaoke box. You won't be the only one doing it, particularly on weekends. In particular, the brand new WiP Internet cafe (http://www.wip-fe.com) on the southwest side of the station is a right gem, offering a 9 hour private booth nightpack for ¥2190, inclusive of shower usage and offers the rare option of staying in a separate non-smoking area.
J-Hoppers Trad Guesthouse
A lively hostel with English speaking staff. Every private room is Japanese style. They also offer free wifi with your laptop ¥100 per 30 min for hostel computers and rental bikes ¥500 per day, with no curfew or lockout and held-luggage services.
Business Ryokan Sansui
Run by Kato-san and her family, this ryokan is quiet and clean, with breakfast available at ¥600. An excellent place to stay if you wish to practice your Japanese and mingle with the locals. Kato-san closes the doors at midnight.
Capsule Inn Hiroshima
Available only for male visitors. Off Aioi-dori, turn left at the corner with a post office. Enter the sixth small street on the left. There are actually two hotels on the both sides of the street. Has a decent sento hot bath for guests.
Hiroshima Town Hotel
Sort of a hybrid of a business hotel and a love hotel, featuring a bewildering array of cheap rates from the 70 minute "shower" ¥2300 up to 20 hours ¥5900. That said, it is clean, convenient, and comfortable.
Hiroshima Youth Hostel
Pretty far from town, but well worth the savings. Kitchen facilities, Internet, and a swimming pool summer only are included in the rate. They do have a tightly-enforced 11PM curfew, though. Take bus #30 from JR Hiroshima Station to Ushita-Shinmachi or the Astram to Fudoin-mae; it's a walk uphill from there. Currently closed, from April 2012 (http://www.city.hiroshima...)
Minshuku Ikedaya
The rooms at this minshuku are clean, bright, and pleasant. The staff speak enough English to get you checked in, although you may not see a trace of them afterward.
Midrange
Chisun Hotel Hiroshima
Bright, new, small rooms. Buffet breakfast is available for ¥1200.
Comfort Hotel Hiroshima
A branch of the American hotel chain, offering Western-style rooms with plenty of business amenities.
Dormy Inn
Centrally located along Heiwa-o-dori, this is a comfortable and friendly full-service hotel with Western-style rooms, free laundry facilities, bike rentals, and a great sento bath. There's a complimentary taxi service from JR Hiroshima Station with advance reservation.
Hiroshima Grand Intelligent Hotel
A tall, pleasant Western-style hotel with a suitably grand lobby and comparatively modest guest rooms. Breakfast is served for ¥1350 buffet, ¥600 toast set. LAN Internet access is available in every room.
Hiroshima Intelligent Hotel Annex
Just down the street from the Grand, with comparable facilities.
Hotel Active!
Cheaper than most business hotels, featuring small but modern, fashionable rooms with LAN Internet access, and helpful, cool staff.
Oriental Hotel Hiroshima
Very stylish 4-star hotel though the outside doesn't look like it. Features a lot of modern Japanese and European art. Make sure to check out the bar on the 23rd floor which is quite pricey but makes up for it with its 360° view of Hiroshima and an interesting ceiling.
Via Inn
A tall business hotel with tiny rooms but a fair number of amenities, including Internet access in the lobby. It's tucked away behind the post office. Head between the coffee shop and the convenience store to find the front desk.
Top end
Aioi Ryokan
The closest traditional Japanese accommodations to the Peace Park, although only the upper floors have a view. Breakfast and dinner are included in the rate, and their versatile kitchen earns rave reviews for dishes high and low on the elegance scale. All of their tastefully appointed rooms have private baths, but there are communal baths on the seventh floor with a memorable view of the A-Bomb Dome.
ANA Crowne Plaza Hiroshima
Great location near the Peace Park, with multiple restaurants, a health club, Internet access, and all the amenities the price would suggest.
Hotel Granvia
Located right outside the Shinkansen gates, this will be the most convenient hotel for any late-arriving travelers. The cheapest single rooms with no meals ¥7600 aren't much more than an average business hotel, but spending time at the elegant lounge and restaurant — and splurging on a luxury twin room with a terrific view ¥22,000 — will raise the price tag.
Hotel Sunroute Hiroshima
Just off Heiwa-odori, the top floors of this tall, modern hotel offer the best views of the Peace Park other than the Rihga Royal below. There are two restaurants Italian and Japanese on-site. The amenities are basic free Internet, but the location is excellent.
Rihga Royal Hiroshima
Overlooking the Peace Park, this luxury hotel is also the tallest building in Hiroshima. There are several restaurants and lounges on premises, and a massive swimming pool/sauna for a fee ¥3150 adults, ¥1575 kids. Baseball fans take note: this is where visiting teams stay when they're in town, so the lobby is a good place to pick up autographs.