World number one Nadal will meet Greek teenager Stefanos Tsitsipas in Sunday's showpiece when he will target a record-extending 11th title in Barcelona a week after claiming the Monte Carlo Masters for the 11th time.
Nadal has won every final he has played in Barcelona.
The Mallorcan got off to a slow start in the semi-final on the Rafael Nadal Court as he surrendered his service in the opening game and 10th-ranked Goffin held to take a 2-0 lead.
Nadal immediately broke back to level and the home favourite broke again in the 10th to take the first set.
The Spaniard came into his own in the second while Goffin, who had to play three sets against Roberto Bautista Agut in the last quarter-final on Friday, began to wilt.
The Belgian finally came out fighting in the sixth game but eventually succumbed to claycourt specialist Nadal, surrendering serve for the third time in the set by firing a shot beyond the baseline, ending a match lasting one hour 22 minutes.