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