Here is the full list of all 50 Persona 4 Golden achievements. It takes around 150-200 hours to unlock all of the achievements on Windows.
Get 50 Sweep Bonuses
Catch the Sea Guardian
Use 4 or more Personas in a special fusion
Finish Aiya's special dish
Max out all social qualities
Max out 10 Social Links
Secure Tohru Adachi
Register over 50% of the Compendium
Rank #1 in your class on an exam
Rescue Nanako Dojima
Go to 3 movies at 30 Frame
Rescue Naoto Shirogane
Deal over 999 damage in 1 attack
Max out a Social Link
Enter a special relationship with someone
Make 5 perfect boxed lunches
Buy an item from the Capsule Machine
Drink the coffee at Chagall Cafe
Buy 5 things from Tanaka's Amazing Commodities
Buy a special croquette from Sozai Daigaku
Secure Mitsuo Kubo
Buy a Persona from the Compendium
Swing the net with perfect timing
Rescue Rise Kujikawa
Switch Personas 5 times in 1 battle
Perform 50 All-Out Attacks
Experience a fusion accident
Win a prize from the vending machine
Rescue Kanji Tatsumi
Register a Skill Card
Exploit enemy weaknesses 100 times
Rescue Yukiko Amagi
Defeat a Golden Hand
Fight a battle in costume
Enter a battle with Player Advantage
Obtain the Persona Izanagi
Earn all trophies
Rescue Marie
Defeat Izanami
Perform 50 Persona fusions
Register 100 Skill Cards
Hear 250 of Rise's navigation lines
Defeat Margaret
Defeat The Reaper
Read all books
Create Izanagi-no-Okami
Complete the Persona Compendium
Max out all Social Links
Visit Nanako in the hospital 3 times
Win the Miracle Quiz Finals