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