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.
Defeat Izanami
Register 100 Skill Cards
Rescue Marie
Catch the Sea Guardian
Win the Miracle Quiz Finals
Secure Tohru Adachi
Max out 10 Social Links
Visit Nanako in the hospital 3 times
Rescue Nanako Dojima
Perform 50 Persona fusions
Finish Aiya's special dish
Max out all social qualities
Go to 3 movies at 30 Frame
Make 5 perfect boxed lunches
Rescue Naoto Shirogane
Deal over 999 damage in 1 attack
Register over 50% of the Compendium
Use 4 or more Personas in a special fusion
Buy a special croquette from Sozai Daigaku
Enter a special relationship with someone
Buy an item from the Capsule Machine
Max out a Social Link
Secure Mitsuo Kubo
Switch Personas 5 times in 1 battle
Drink the coffee at Chagall Cafe
Rank #1 in your class on an exam
Buy 5 things from Tanaka's Amazing Commodities
Rescue Rise Kujikawa
Experience a fusion accident
Swing the net with perfect timing
Rescue Kanji Tatsumi
Get 50 Sweep Bonuses
Buy a Persona from the Compendium
Perform 50 All-Out Attacks
Exploit enemy weaknesses 100 times
Register a Skill Card
Rescue Yukiko Amagi
Defeat a Golden Hand
Win a prize from the vending machine
Fight a battle in costume
Enter a battle with Player Advantage
Obtain the Persona Izanagi
Earn all trophies
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