The group described Aucoin, 66, as "our irreplacable original manager, mentor and dear friend."
"He was instrumental in guiding us from the beginning and without his vision, leadership and unending dedication, we could never have scaled the heights we have reached," KISS said in its posting.
The band remembered Aucoin as someone who "loved life and lived it to the fullest."
"Words can never convey his impact on us or those close to him," the message said. "Over all the years, he never missed an opportunity to be with us at our shows near his home or fly in for special concerts, including our most recent Madison Square Garden show. He had hoped to attend our London show earlier this month but his illness prevented it. He still planned to visit us upon the start of our upcoming U.S. tour. We loved him, told him and have peace that he knew it. We will grieve and celebrate all he was and did. We have lost a part of us."
Despite the band's characterization of Aucoin as its "original manager," Lew Linet said he, Simmons and Stanley actually hired Peter Criss and Ace Frehley at the end of 1972 and formed KISS.
"I was personal manager first to (Simmons and Stanley's band) Wicked Lester and then to KISS. I worked with the band in New York for a number of months in 1973 and then left the band for artistic reasons," Linet told UPI in an email. "They then found Bill Aucoin, who did a magnificent job taking them the rest of the way."