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